tools: roll inspector_protocol to f67ec5

Fixes: https://github.com/nodejs/node/issues/25808

PR-URL: https://github.com/nodejs/node/pull/26303
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>

31 files changed, 2470 insertions, 264 deletions

diff --git a/tools/inspector_protocol/README.v8 b/tools/inspector_protocol/README.node
index 8a82f2a9c9..6f22020a4d 100644
--- a/tools/inspector_protocol/README.v8
+++ b/tools/inspector_protocol/README.node
@@ -2,7 +2,7 @@ Name: inspector protocol
 Short Name: inspector_protocol
 URL: https://chromium.googlesource.com/deps/inspector_protocol/
 Version: 0
-Revision: 752d4abd13119010cf30e454e8ef9b5fb7ef43a3
+Revision: f67ec5180f476830e839226b5ca948e43070fdab
 License: BSD
 License File: LICENSE
 Security Critical: no
diff --git a/tools/inspector_protocol/CheckProtocolCompatibility.py b/tools/inspector_protocol/check_protocol_compatibility.py
index c70162a2a4..d2df244fa9 100755
--- a/tools/inspector_protocol/CheckProtocolCompatibility.py
+++ b/tools/inspector_protocol/check_protocol_compatibility.py
@@ -45,11 +45,14 @@
 #
 # Adding --show_changes to the command line prints out a list of valid public API changes.
 
+from __future__ import print_function
 import copy
 import os.path
 import optparse
 import sys
 
+import pdl
+
 try:
     import json
 except ImportError:
@@ -166,6 +169,11 @@ def compare_types(context, kind, type_1, type_2, types_map_1, types_map_2, depth
     base_type_1 = type_1["type"]
     base_type_2 = type_2["type"]
 
+    # Binary and string have the same wire representation in JSON.
+    if ((base_type_1 == "string" and base_type_2 == "binary") or
+        (base_type_2 == "string" and base_type_1 == "binary")):
+      return
+
     if base_type_1 != base_type_2:
         errors.append("%s: %s base type mismatch, '%s' vs '%s'" % (context, kind, base_type_1, base_type_2))
     elif base_type_1 == "object":
@@ -228,8 +236,8 @@ def load_schema(file_name, domains):
     if not os.path.isfile(file_name):
         return
     input_file = open(file_name, "r")
-    json_string = input_file.read()
-    parsed_json = json.loads(json_string)
+    parsed_json = pdl.loads(input_file.read(), file_name)
+    input_file.close()
     domains += parsed_json["domains"]
     return parsed_json["version"]
 
@@ -422,6 +430,7 @@ def load_domains_and_baselines(file_name, domains, baseline_domains):
     version = load_schema(os.path.normpath(file_name), domains)
     suffix = "-%s.%s.json" % (version["major"], version["minor"])
     baseline_file = file_name.replace(".json", suffix)
+    baseline_file = file_name.replace(".pdl", suffix)
     load_schema(os.path.normpath(baseline_file), baseline_domains)
     return version
 
@@ -467,9 +476,9 @@ def main():
     if arg_options.show_changes:
         changes = compare_schemas(domains, baseline_domains, True)
         if len(changes) > 0:
-            print "  Public changes since %s:" % version
+            print("  Public changes since %s:" % version)
             for change in changes:
-                print "    %s" % change
+                print("    %s" % change)
 
     if arg_options.stamp:
         with open(arg_options.stamp, 'a') as _:
diff --git a/tools/inspector_protocol/CodeGenerator.py b/tools/inspector_protocol/code_generator.py
index e630b02985..fb9959d608 100644..100755
--- a/tools/inspector_protocol/CodeGenerator.py
+++ b/tools/inspector_protocol/code_generator.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
@@ -14,6 +15,8 @@ try:
 except ImportError:
     import simplejson as json
 
+import pdl
+
 # Path handling for libraries and templates
 # Paths have to be normalized because Jinja uses the exact template path to
 # determine the hash used in the cache filename, and we need a pre-caching step
@@ -30,14 +33,14 @@ def read_config():
         def json_object_hook(object_dict):
             items = [(k, os.path.join(config_base, v) if k == "path" else v) for (k, v) in object_dict.items()]
             items = [(k, os.path.join(output_base, v) if k == "output" else v) for (k, v) in items]
-            keys, values = zip(*items)
+            keys, values = list(zip(*items))
             return collections.namedtuple('X', keys)(*values)
         return json.loads(data, object_hook=json_object_hook)
 
     def init_defaults(config_tuple, path, defaults):
         keys = list(config_tuple._fields)  # pylint: disable=E1101
         values = [getattr(config_tuple, k) for k in keys]
-        for i in xrange(len(keys)):
+        for i in range(len(keys)):
             if hasattr(values[i], "_fields"):
                 values[i] = init_defaults(values[i], path + "." + keys[i], defaults)
         for optional in defaults:
@@ -95,6 +98,7 @@ def read_config():
             ".protocol.export_macro": "",
             ".protocol.export_header": False,
             ".protocol.options": False,
+            ".protocol.file_name_prefix": "",
             ".exported": False,
             ".exported.export_macro": "",
             ".exported.export_header": False,
@@ -130,7 +134,7 @@ def dash_to_camelcase(word):
 
 
 def to_snake_case(name):
-    return re.sub(r"([a-z0-9])([A-Z])", r"\1_\2", name, sys.maxint).lower()
+    return re.sub(r"([a-z0-9])([A-Z])", r"\1_\2", name, sys.maxsize).lower()
 
 
 def to_method_case(config, name):
@@ -156,6 +160,10 @@ def format_include(config, header, file_name=None):
     return header
 
 
+def format_domain_include(config, header, file_name):
+    return format_include(config, header, config.protocol.file_name_prefix + file_name)
+
+
 def to_file_name(config, file_name):
     if config.use_snake_file_names:
         return to_snake_case(file_name).replace(".cpp", ".cc")
@@ -258,6 +266,21 @@ def create_string_type_definition():
     }
 
 
+def create_binary_type_definition():
+    # pylint: disable=W0622
+    return {
+        "return_type": "Binary",
+        "pass_type": "const Binary&",
+        "to_pass_type": "%s",
+        "to_raw_type": "%s",
+        "to_rvalue": "%s",
+        "type": "Binary",
+        "raw_type": "Binary",
+        "raw_pass_type": "const Binary&",
+        "raw_return_type": "Binary",
+    }
+
+
 def create_primitive_type_definition(type):
     # pylint: disable=W0622
     typedefs = {
@@ -330,9 +353,8 @@ class Protocol(object):
 
     def read_protocol_file(self, file_name):
         input_file = open(file_name, "r")
-        json_string = input_file.read()
+        parsed_json = pdl.loads(input_file.read(), file_name)
         input_file.close()
-        parsed_json = json.loads(json_string)
         version = parsed_json["version"]["major"] + "." + parsed_json["version"]["minor"]
         domains = []
         for domain in parsed_json["domains"]:
@@ -436,8 +458,10 @@ class Protocol(object):
         self.type_definitions["boolean"] = create_primitive_type_definition("boolean")
         self.type_definitions["object"] = create_object_type_definition()
         self.type_definitions["any"] = create_any_type_definition()
+        self.type_definitions["binary"] = create_binary_type_definition()
         for domain in self.json_api["domains"]:
             self.type_definitions[domain["domain"] + ".string"] = create_string_type_definition()
+            self.type_definitions[domain["domain"] + ".binary"] = create_binary_type_definition()
             if not ("types" in domain):
                 continue
             for type in domain["types"]:
@@ -447,10 +471,11 @@ class Protocol(object):
                 elif type["type"] == "object":
                     self.type_definitions[type_name] = create_user_type_definition(domain["domain"], type)
                 elif type["type"] == "array":
-                    items_type = type["items"]["type"]
-                    self.type_definitions[type_name] = wrap_array_definition(self.type_definitions[items_type])
+                    self.type_definitions[type_name] = self.resolve_type(type)
                 elif type["type"] == domain["domain"] + ".string":
                     self.type_definitions[type_name] = create_string_type_definition()
+                elif type["type"] == domain["domain"] + ".binary":
+                    self.type_definitions[type_name] = create_binary_type_definition()
                 else:
                     self.type_definitions[type_name] = create_primitive_type_definition(type["type"])
 
@@ -571,21 +596,23 @@ def main():
 
     for domain in protocol.json_api["domains"]:
         class_name = domain["domain"]
+        file_name = config.protocol.file_name_prefix + class_name
         template_context = {
             "protocol": protocol,
             "config": config,
             "domain": domain,
             "join_arrays": join_arrays,
             "format_include": functools.partial(format_include, config),
+            "format_domain_include": functools.partial(format_domain_include, config),
         }
 
         if domain["domain"] in protocol.generate_domains:
-            outputs[os.path.join(config.protocol.output, to_file_name(config, class_name + ".h"))] = h_template.render(template_context)
-            outputs[os.path.join(config.protocol.output, to_file_name(config, class_name + ".cpp"))] = cpp_template.render(template_context)
+            outputs[os.path.join(config.protocol.output, to_file_name(config, file_name + ".h"))] = h_template.render(template_context)
+            outputs[os.path.join(config.protocol.output, to_file_name(config, file_name + ".cpp"))] = cpp_template.render(template_context)
             if domain["domain"] in protocol.exported_domains:
-                outputs[os.path.join(config.exported.output, to_file_name(config, class_name + ".h"))] = exported_template.render(template_context)
+                outputs[os.path.join(config.exported.output, to_file_name(config, file_name + ".h"))] = exported_template.render(template_context)
         if domain["domain"] in protocol.imported_domains:
-            outputs[os.path.join(config.protocol.output, to_file_name(config, class_name + ".h"))] = imported_template.render(template_context)
+            outputs[os.path.join(config.protocol.output, to_file_name(config, file_name + ".h"))] = imported_template.render(template_context)
 
     if config.lib:
         template_context = {
@@ -596,8 +623,7 @@ def main():
         lib_templates_dir = os.path.join(module_path, "lib")
         # Note these should be sorted in the right order.
         # TODO(dgozman): sort them programmatically based on commented includes.
-        lib_h_templates = [
-            "Collections_h.template",
+        protocol_h_templates = [
             "ErrorSupport_h.template",
             "Values_h.template",
             "Object_h.template",
@@ -606,15 +632,17 @@ def main():
             "Array_h.template",
             "DispatcherBase_h.template",
             "Parser_h.template",
+            "CBOR_h.template",
         ]
 
-        lib_cpp_templates = [
+        protocol_cpp_templates = [
             "Protocol_cpp.template",
             "ErrorSupport_cpp.template",
             "Values_cpp.template",
             "Object_cpp.template",
             "DispatcherBase_cpp.template",
             "Parser_cpp.template",
+            "CBOR_cpp.template",
         ]
 
         forward_h_templates = [
@@ -623,6 +651,14 @@ def main():
             "FrontendChannel_h.template",
         ]
 
+        base_string_adapter_h_templates = [
+            "base_string_adapter_h.template",
+        ]
+
+        base_string_adapter_cc_templates = [
+            "base_string_adapter_cc.template",
+        ]
+
         def generate_lib_file(file_name, template_files):
             parts = []
             for template_file in template_files:
@@ -632,20 +668,22 @@ def main():
             outputs[file_name] = "\n\n".join(parts)
 
         generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "Forward.h")), forward_h_templates)
-        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "Protocol.h")), lib_h_templates)
-        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "Protocol.cpp")), lib_cpp_templates)
+        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "Protocol.h")), protocol_h_templates)
+        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "Protocol.cpp")), protocol_cpp_templates)
+        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "base_string_adapter.h")), base_string_adapter_h_templates)
+        generate_lib_file(os.path.join(config.lib.output, to_file_name(config, "base_string_adapter.cc")), base_string_adapter_cc_templates)
 
     # Make gyp / make generatos happy, otherwise make rebuilds world.
     inputs_ts = max(map(os.path.getmtime, inputs))
     up_to_date = True
-    for output_file in outputs.iterkeys():
+    for output_file in outputs.keys():
         if not os.path.exists(output_file) or os.path.getmtime(output_file) < inputs_ts:
             up_to_date = False
             break
     if up_to_date:
         sys.exit()
 
-    for file_name, content in outputs.iteritems():
+    for file_name, content in outputs.items():
         out_file = open(file_name, "w")
         out_file.write(content)
         out_file.close()
diff --git a/tools/inspector_protocol/ConcatenateProtocols.py b/tools/inspector_protocol/concatenate_protocols.py
index a7cbc992c7..e9f448efe7 100755
--- a/tools/inspector_protocol/ConcatenateProtocols.py
+++ b/tools/inspector_protocol/concatenate_protocols.py
@@ -11,6 +11,7 @@ try:
 except ImportError:
     import simplejson as json
 
+import pdl
 
 def main(argv):
     if len(argv) < 1:
@@ -25,8 +26,7 @@ def main(argv):
             sys.stderr.write("Cannot find %s\n" % file_name)
             return 1
         input_file = open(file_name, "r")
-        json_string = input_file.read()
-        parsed_json = json.loads(json_string)
+        parsed_json = pdl.loads(input_file.read(), file_name)
         domains += parsed_json["domains"]
         version = parsed_json["version"]
 
diff --git a/tools/inspector_protocol/convert_protocol_to_json.py b/tools/inspector_protocol/convert_protocol_to_json.py
new file mode 100755
index 0000000000..96048f793d
--- /dev/null
+++ b/tools/inspector_protocol/convert_protocol_to_json.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import collections
+import json
+import os.path
+import re
+import sys
+
+import pdl
+
+def main(argv):
+    parser = argparse.ArgumentParser(description=(
+        "Converts from .pdl to .json by invoking the pdl Python module."))
+    parser.add_argument('--map_binary_to_string', type=bool,
+                        help=('If set, binary in the .pdl is mapped to a '
+                              'string in .json. Client code will have to '
+                              'base64 decode the string to get the payload.'))
+    parser.add_argument("pdl_file", help="The .pdl input file to parse.")
+    parser.add_argument("json_file", help="The .json output file write.")
+    args = parser.parse_args(argv)
+    file_name = os.path.normpath(args.pdl_file)
+    input_file = open(file_name, "r")
+    pdl_string = input_file.read()
+    protocol = pdl.loads(pdl_string, file_name, args.map_binary_to_string)
+    input_file.close()
+
+    output_file = open(os.path.normpath(args.json_file), 'wb')
+    json.dump(protocol, output_file, indent=4, separators=(',', ': '))
+    output_file.close()
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv[1:]))
diff --git a/tools/inspector_protocol/lib/Allocator_h.template b/tools/inspector_protocol/lib/Allocator_h.template
index 8f8109d695..15eaaaff02 100644
--- a/tools/inspector_protocol/lib/Allocator_h.template
+++ b/tools/inspector_protocol/lib/Allocator_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Allocator_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -11,13 +13,6 @@ namespace {{namespace}} {
 
 enum NotNullTagEnum { NotNullLiteral };
 
-#define PROTOCOL_DISALLOW_NEW()                                 \
-    private:                                                    \
-        void* operator new(size_t) = delete;                    \
-        void* operator new(size_t, NotNullTagEnum, void*) = delete; \
-        void* operator new(size_t, void*) = delete;             \
-    public:
-
 #define PROTOCOL_DISALLOW_COPY(ClassName) \
     private: \
         ClassName(const ClassName&) = delete; \
diff --git a/tools/inspector_protocol/lib/Array_h.template b/tools/inspector_protocol/lib/Array_h.template
index 3854f6e5cd..c420a0f7e9 100644
--- a/tools/inspector_protocol/lib/Array_h.template
+++ b/tools/inspector_protocol/lib/Array_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Array_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
diff --git a/tools/inspector_protocol/lib/CBOR_cpp.template b/tools/inspector_protocol/lib/CBOR_cpp.template
new file mode 100644
index 0000000000..36750b19a3
--- /dev/null
+++ b/tools/inspector_protocol/lib/CBOR_cpp.template
@@ -0,0 +1,803 @@
+{# This template is generated by gen_cbor_templates.py. #}
+// Generated by lib/CBOR_cpp.template.
+
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+#include <cassert>
+#include <limits>
+
+{% for namespace in config.protocol.namespace %}
+namespace {{namespace}} {
+{% endfor %}
+
+// ===== encoding/cbor.cc =====
+
+using namespace cbor;
+
+namespace {
+
+// See RFC 7049 Section 2.3, Table 2.
+static constexpr uint8_t kEncodedTrue =
+    EncodeInitialByte(MajorType::SIMPLE_VALUE, 21);
+static constexpr uint8_t kEncodedFalse =
+    EncodeInitialByte(MajorType::SIMPLE_VALUE, 20);
+static constexpr uint8_t kEncodedNull =
+    EncodeInitialByte(MajorType::SIMPLE_VALUE, 22);
+static constexpr uint8_t kInitialByteForDouble =
+    EncodeInitialByte(MajorType::SIMPLE_VALUE, 27);
+
+}  // namespace
+
+uint8_t EncodeTrue() { return kEncodedTrue; }
+uint8_t EncodeFalse() { return kEncodedFalse; }
+uint8_t EncodeNull() { return kEncodedNull; }
+
+uint8_t EncodeIndefiniteLengthArrayStart() {
+  return kInitialByteIndefiniteLengthArray;
+}
+
+uint8_t EncodeIndefiniteLengthMapStart() {
+  return kInitialByteIndefiniteLengthMap;
+}
+
+uint8_t EncodeStop() { return kStopByte; }
+
+namespace {
+// See RFC 7049 Table 3 and Section 2.4.4.2. This is used as a prefix for
+// arbitrary binary data encoded as BYTE_STRING.
+static constexpr uint8_t kExpectedConversionToBase64Tag =
+    EncodeInitialByte(MajorType::TAG, 22);
+
+// When parsing CBOR, we limit recursion depth for objects and arrays
+// to this constant.
+static constexpr int kStackLimit = 1000;
+
+// Writes the bytes for |v| to |out|, starting with the most significant byte.
+// See also: https://commandcenter.blogspot.com/2012/04/byte-order-fallacy.html
+template <typename T>
+void WriteBytesMostSignificantByteFirst(T v, std::vector<uint8_t>* out) {
+  for (int shift_bytes = sizeof(T) - 1; shift_bytes >= 0; --shift_bytes)
+    out->push_back(0xff & (v >> (shift_bytes * 8)));
+}
+}  // namespace
+
+namespace cbor_internals {
+// Writes the start of a token with |type|. The |value| may indicate the size,
+// or it may be the payload if the value is an unsigned integer.
+void WriteTokenStart(MajorType type, uint64_t value,
+                     std::vector<uint8_t>* encoded) {
+  if (value < 24) {
+    // Values 0-23 are encoded directly into the additional info of the
+    // initial byte.
+    encoded->push_back(EncodeInitialByte(type, /*additional_info=*/value));
+    return;
+  }
+  if (value <= std::numeric_limits<uint8_t>::max()) {
+    // Values 24-255 are encoded with one initial byte, followed by the value.
+    encoded->push_back(EncodeInitialByte(type, kAdditionalInformation1Byte));
+    encoded->push_back(value);
+    return;
+  }
+  if (value <= std::numeric_limits<uint16_t>::max()) {
+    // Values 256-65535: 1 initial byte + 2 bytes payload.
+    encoded->push_back(EncodeInitialByte(type, kAdditionalInformation2Bytes));
+    WriteBytesMostSignificantByteFirst<uint16_t>(value, encoded);
+    return;
+  }
+  if (value <= std::numeric_limits<uint32_t>::max()) {
+    // 32 bit uint: 1 initial byte + 4 bytes payload.
+    encoded->push_back(EncodeInitialByte(type, kAdditionalInformation4Bytes));
+    WriteBytesMostSignificantByteFirst<uint32_t>(static_cast<uint32_t>(value),
+                                                 encoded);
+    return;
+  }
+  // 64 bit uint: 1 initial byte + 8 bytes payload.
+  encoded->push_back(EncodeInitialByte(type, kAdditionalInformation8Bytes));
+  WriteBytesMostSignificantByteFirst<uint64_t>(value, encoded);
+}
+}  // namespace cbor_internals
+
+namespace {
+// Extracts sizeof(T) bytes from |in| to extract a value of type T
+// (e.g. uint64_t, uint32_t, ...), most significant byte first.
+// See also: https://commandcenter.blogspot.com/2012/04/byte-order-fallacy.html
+template <typename T>
+T ReadBytesMostSignificantByteFirst(span<uint8_t> in) {
+  assert(static_cast<std::size_t>(in.size()) >= sizeof(T));
+  T result = 0;
+  for (std::size_t shift_bytes = 0; shift_bytes < sizeof(T); ++shift_bytes)
+    result |= T(in[sizeof(T) - 1 - shift_bytes]) << (shift_bytes * 8);
+  return result;
+}
+}  // namespace
+
+namespace cbor_internals {
+int8_t ReadTokenStart(span<uint8_t> bytes, MajorType* type, uint64_t* value) {
+  if (bytes.empty()) return -1;
+  uint8_t initial_byte = bytes[0];
+  *type = MajorType((initial_byte & kMajorTypeMask) >> kMajorTypeBitShift);
+
+  uint8_t additional_information = initial_byte & kAdditionalInformationMask;
+  if (additional_information < 24) {
+    // Values 0-23 are encoded directly into the additional info of the
+    // initial byte.
+    *value = additional_information;
+    return 1;
+  }
+  if (additional_information == kAdditionalInformation1Byte) {
+    // Values 24-255 are encoded with one initial byte, followed by the value.
+    if (bytes.size() < 2) return -1;
+    *value = ReadBytesMostSignificantByteFirst<uint8_t>(bytes.subspan(1));
+    return 2;
+  }
+  if (additional_information == kAdditionalInformation2Bytes) {
+    // Values 256-65535: 1 initial byte + 2 bytes payload.
+    if (static_cast<std::size_t>(bytes.size()) < 1 + sizeof(uint16_t))
+      return -1;
+    *value = ReadBytesMostSignificantByteFirst<uint16_t>(bytes.subspan(1));
+    return 3;
+  }
+  if (additional_information == kAdditionalInformation4Bytes) {
+    // 32 bit uint: 1 initial byte + 4 bytes payload.
+    if (static_cast<std::size_t>(bytes.size()) < 1 + sizeof(uint32_t))
+      return -1;
+    *value = ReadBytesMostSignificantByteFirst<uint32_t>(bytes.subspan(1));
+    return 5;
+  }
+  if (additional_information == kAdditionalInformation8Bytes) {
+    // 64 bit uint: 1 initial byte + 8 bytes payload.
+    if (static_cast<std::size_t>(bytes.size()) < 1 + sizeof(uint64_t))
+      return -1;
+    *value = ReadBytesMostSignificantByteFirst<uint64_t>(bytes.subspan(1));
+    return 9;
+  }
+  return -1;
+}
+}  // namespace cbor_internals
+
+using cbor_internals::WriteTokenStart;
+using cbor_internals::ReadTokenStart;
+
+void EncodeInt32(int32_t value, std::vector<uint8_t>* out) {
+  if (value >= 0) {
+    WriteTokenStart(MajorType::UNSIGNED, value, out);
+  } else {
+    uint64_t representation = static_cast<uint64_t>(-(value + 1));
+    WriteTokenStart(MajorType::NEGATIVE, representation, out);
+  }
+}
+
+void EncodeString16(span<uint16_t> in, std::vector<uint8_t>* out) {
+  uint64_t byte_length = static_cast<uint64_t>(in.size_bytes());
+  WriteTokenStart(MajorType::BYTE_STRING, byte_length, out);
+  // When emitting UTF16 characters, we always write the least significant byte
+  // first; this is because it's the native representation for X86.
+  // TODO(johannes): Implement a more efficient thing here later, e.g.
+  // casting *iff* the machine has this byte order.
+  // The wire format for UTF16 chars will probably remain the same
+  // (least significant byte first) since this way we can have
+  // golden files, unittests, etc. that port easily and universally.
+  // See also:
+  // https://commandcenter.blogspot.com/2012/04/byte-order-fallacy.html
+  for (const uint16_t two_bytes : in) {
+    out->push_back(two_bytes);
+    out->push_back(two_bytes >> 8);
+  }
+}
+
+void EncodeString8(span<uint8_t> in, std::vector<uint8_t>* out) {
+  WriteTokenStart(MajorType::STRING, static_cast<uint64_t>(in.size_bytes()),
+                  out);
+  out->insert(out->end(), in.begin(), in.end());
+}
+
+void EncodeBinary(span<uint8_t> in, std::vector<uint8_t>* out) {
+  out->push_back(kExpectedConversionToBase64Tag);
+  uint64_t byte_length = static_cast<uint64_t>(in.size_bytes());
+  WriteTokenStart(MajorType::BYTE_STRING, byte_length, out);
+  out->insert(out->end(), in.begin(), in.end());
+}
+
+// A double is encoded with a specific initial byte
+// (kInitialByteForDouble) plus the 64 bits of payload for its value.
+constexpr std::ptrdiff_t kEncodedDoubleSize = 1 + sizeof(uint64_t);
+
+// An envelope is encoded with a specific initial byte
+// (kInitialByteForEnvelope), plus the start byte for a BYTE_STRING with a 32
+// bit wide length, plus a 32 bit length for that string.
+constexpr std::ptrdiff_t kEncodedEnvelopeHeaderSize = 1 + 1 + sizeof(uint32_t);
+
+void EncodeDouble(double value, std::vector<uint8_t>* out) {
+  // The additional_info=27 indicates 64 bits for the double follow.
+  // See RFC 7049 Section 2.3, Table 1.
+  out->push_back(kInitialByteForDouble);
+  union {
+    double from_double;
+    uint64_t to_uint64;
+  } reinterpret;
+  reinterpret.from_double = value;
+  WriteBytesMostSignificantByteFirst<uint64_t>(reinterpret.to_uint64, out);
+}
+
+void EnvelopeEncoder::EncodeStart(std::vector<uint8_t>* out) {
+  assert(byte_size_pos_ == 0);
+  out->push_back(kInitialByteForEnvelope);
+  out->push_back(kInitialByteFor32BitLengthByteString);
+  byte_size_pos_ = out->size();
+  out->resize(out->size() + sizeof(uint32_t));
+}
+
+bool EnvelopeEncoder::EncodeStop(std::vector<uint8_t>* out) {
+  assert(byte_size_pos_ != 0);
+  // The byte size is the size of the payload, that is, all the
+  // bytes that were written past the byte size position itself.
+  uint64_t byte_size = out->size() - (byte_size_pos_ + sizeof(uint32_t));
+  // We store exactly 4 bytes, so at most INT32MAX, with most significant
+  // byte first.
+  if (byte_size > std::numeric_limits<uint32_t>::max()) return false;
+  for (int shift_bytes = sizeof(uint32_t) - 1; shift_bytes >= 0;
+       --shift_bytes) {
+    (*out)[byte_size_pos_++] = 0xff & (byte_size >> (shift_bytes * 8));
+  }
+  return true;
+}
+
+namespace {
+class JSONToCBOREncoder : public JSONParserHandler {
+ public:
+  JSONToCBOREncoder(std::vector<uint8_t>* out, Status* status)
+      : out_(out), status_(status) {
+    *status_ = Status();
+  }
+
+  void HandleObjectBegin() override {
+    envelopes_.emplace_back();
+    envelopes_.back().EncodeStart(out_);
+    out_->push_back(kInitialByteIndefiniteLengthMap);
+  }
+
+  void HandleObjectEnd() override {
+    out_->push_back(kStopByte);
+    assert(!envelopes_.empty());
+    envelopes_.back().EncodeStop(out_);
+    envelopes_.pop_back();
+  }
+
+  void HandleArrayBegin() override {
+    envelopes_.emplace_back();
+    envelopes_.back().EncodeStart(out_);
+    out_->push_back(kInitialByteIndefiniteLengthArray);
+  }
+
+  void HandleArrayEnd() override {
+    out_->push_back(kStopByte);
+    assert(!envelopes_.empty());
+    envelopes_.back().EncodeStop(out_);
+    envelopes_.pop_back();
+  }
+
+  void HandleString16(std::vector<uint16_t> chars) override {
+    for (uint16_t ch : chars) {
+      if (ch >= 0x7f) {
+        // If there's at least one non-7bit character, we encode as UTF16.
+        EncodeString16(span<uint16_t>(chars.data(), chars.size()), out_);
+        return;
+      }
+    }
+    std::vector<uint8_t> sevenbit_chars(chars.begin(), chars.end());
+    EncodeString8(span<uint8_t>(sevenbit_chars.data(), sevenbit_chars.size()),
+                  out_);
+  }
+
+  void HandleBinary(std::vector<uint8_t> bytes) override {
+    EncodeBinary(span<uint8_t>(bytes.data(), bytes.size()), out_);
+  }
+
+  void HandleDouble(double value) override { EncodeDouble(value, out_); }
+
+  void HandleInt32(int32_t value) override { EncodeInt32(value, out_); }
+
+  void HandleBool(bool value) override {
+    // See RFC 7049 Section 2.3, Table 2.
+    out_->push_back(value ? kEncodedTrue : kEncodedFalse);
+  }
+
+  void HandleNull() override {
+    // See RFC 7049 Section 2.3, Table 2.
+    out_->push_back(kEncodedNull);
+  }
+
+  void HandleError(Status error) override {
+    assert(!error.ok());
+    *status_ = error;
+    out_->clear();
+  }
+
+ private:
+  std::vector<uint8_t>* out_;
+  std::vector<EnvelopeEncoder> envelopes_;
+  Status* status_;
+};
+}  // namespace
+
+std::unique_ptr<JSONParserHandler> NewJSONToCBOREncoder(
+    std::vector<uint8_t>* out, Status* status) {
+  return std::unique_ptr<JSONParserHandler>(new JSONToCBOREncoder(out, status));
+}
+
+namespace {
+// Below are three parsing routines for CBOR, which cover enough
+// to roundtrip JSON messages.
+bool ParseMap(int32_t stack_depth, CBORTokenizer* tokenizer,
+              JSONParserHandler* out);
+bool ParseArray(int32_t stack_depth, CBORTokenizer* tokenizer,
+                JSONParserHandler* out);
+bool ParseValue(int32_t stack_depth, CBORTokenizer* tokenizer,
+                JSONParserHandler* out);
+
+void ParseUTF16String(CBORTokenizer* tokenizer, JSONParserHandler* out) {
+  std::vector<uint16_t> value;
+  span<uint8_t> rep = tokenizer->GetString16WireRep();
+  for (std::ptrdiff_t ii = 0; ii < rep.size(); ii += 2)
+    value.push_back((rep[ii + 1] << 8) | rep[ii]);
+  out->HandleString16(std::move(value));
+  tokenizer->Next();
+}
+
+// For now this method only covers US-ASCII. Later, we may allow UTF8.
+bool ParseASCIIString(CBORTokenizer* tokenizer, JSONParserHandler* out) {
+  assert(tokenizer->TokenTag() == CBORTokenTag::STRING8);
+  std::vector<uint16_t> value16;
+  for (uint8_t ch : tokenizer->GetString8()) {
+    // We only accept us-ascii (7 bit) strings here. Other strings must
+    // be encoded with 16 bit (the BYTE_STRING case).
+    if (ch >= 0x7f) {
+      out->HandleError(
+          Status{Error::CBOR_STRING8_MUST_BE_7BIT, tokenizer->Status().pos});
+      return false;
+    }
+    value16.push_back(ch);
+  }
+  out->HandleString16(std::move(value16));
+  tokenizer->Next();
+  return true;
+}
+
+bool ParseValue(int32_t stack_depth, CBORTokenizer* tokenizer,
+                JSONParserHandler* out) {
+  if (stack_depth > kStackLimit) {
+    out->HandleError(
+        Status{Error::CBOR_STACK_LIMIT_EXCEEDED, tokenizer->Status().pos});
+    return false;
+  }
+  // Skip past the envelope to get to what's inside.
+  if (tokenizer->TokenTag() == CBORTokenTag::ENVELOPE)
+    tokenizer->EnterEnvelope();
+  switch (tokenizer->TokenTag()) {
+    case CBORTokenTag::ERROR_VALUE:
+      out->HandleError(tokenizer->Status());
+      return false;
+    case CBORTokenTag::DONE:
+      out->HandleError(Status{Error::CBOR_UNEXPECTED_EOF_EXPECTED_VALUE,
+                              tokenizer->Status().pos});
+      return false;
+    case CBORTokenTag::TRUE_VALUE:
+      out->HandleBool(true);
+      tokenizer->Next();
+      return true;
+    case CBORTokenTag::FALSE_VALUE:
+      out->HandleBool(false);
+      tokenizer->Next();
+      return true;
+    case CBORTokenTag::NULL_VALUE:
+      out->HandleNull();
+      tokenizer->Next();
+      return true;
+    case CBORTokenTag::INT32:
+      out->HandleInt32(tokenizer->GetInt32());
+      tokenizer->Next();
+      return true;
+    case CBORTokenTag::DOUBLE:
+      out->HandleDouble(tokenizer->GetDouble());
+      tokenizer->Next();
+      return true;
+    case CBORTokenTag::STRING8:
+      return ParseASCIIString(tokenizer, out);
+    case CBORTokenTag::STRING16:
+      ParseUTF16String(tokenizer, out);
+      return true;
+    case CBORTokenTag::BINARY: {
+      span<uint8_t> binary = tokenizer->GetBinary();
+      out->HandleBinary(std::vector<uint8_t>(binary.begin(), binary.end()));
+      tokenizer->Next();
+      return true;
+    }
+    case CBORTokenTag::MAP_START:
+      return ParseMap(stack_depth + 1, tokenizer, out);
+    case CBORTokenTag::ARRAY_START:
+      return ParseArray(stack_depth + 1, tokenizer, out);
+    default:
+      out->HandleError(
+          Status{Error::CBOR_UNSUPPORTED_VALUE, tokenizer->Status().pos});
+      return false;
+  }
+}
+
+// |bytes| must start with the indefinite length array byte, so basically,
+// ParseArray may only be called after an indefinite length array has been
+// detected.
+bool ParseArray(int32_t stack_depth, CBORTokenizer* tokenizer,
+                JSONParserHandler* out) {
+  assert(tokenizer->TokenTag() == CBORTokenTag::ARRAY_START);
+  tokenizer->Next();
+  out->HandleArrayBegin();
+  while (tokenizer->TokenTag() != CBORTokenTag::STOP) {
+    if (tokenizer->TokenTag() == CBORTokenTag::DONE) {
+      out->HandleError(
+          Status{Error::CBOR_UNEXPECTED_EOF_IN_ARRAY, tokenizer->Status().pos});
+      return false;
+    }
+    if (tokenizer->TokenTag() == CBORTokenTag::ERROR_VALUE) {
+      out->HandleError(tokenizer->Status());
+      return false;
+    }
+    // Parse value.
+    if (!ParseValue(stack_depth, tokenizer, out)) return false;
+  }
+  out->HandleArrayEnd();
+  tokenizer->Next();
+  return true;
+}
+
+// |bytes| must start with the indefinite length array byte, so basically,
+// ParseArray may only be called after an indefinite length array has been
+// detected.
+bool ParseMap(int32_t stack_depth, CBORTokenizer* tokenizer,
+              JSONParserHandler* out) {
+  assert(tokenizer->TokenTag() == CBORTokenTag::MAP_START);
+  out->HandleObjectBegin();
+  tokenizer->Next();
+  while (tokenizer->TokenTag() != CBORTokenTag::STOP) {
+    if (tokenizer->TokenTag() == CBORTokenTag::DONE) {
+      out->HandleError(
+          Status{Error::CBOR_UNEXPECTED_EOF_IN_MAP, tokenizer->Status().pos});
+      return false;
+    }
+    if (tokenizer->TokenTag() == CBORTokenTag::ERROR_VALUE) {
+      out->HandleError(tokenizer->Status());
+      return false;
+    }
+    // Parse key.
+    if (tokenizer->TokenTag() == CBORTokenTag::STRING8) {
+      if (!ParseASCIIString(tokenizer, out)) return false;
+    } else if (tokenizer->TokenTag() == CBORTokenTag::STRING16) {
+      ParseUTF16String(tokenizer, out);
+    } else {
+      out->HandleError(
+          Status{Error::CBOR_INVALID_MAP_KEY, tokenizer->Status().pos});
+      return false;
+    }
+    // Parse value.
+    if (!ParseValue(stack_depth, tokenizer, out)) return false;
+  }
+  out->HandleObjectEnd();
+  tokenizer->Next();
+  return true;
+}
+}  // namespace
+
+void ParseCBOR(span<uint8_t> bytes, JSONParserHandler* json_out) {
+  if (bytes.empty()) {
+    json_out->HandleError(Status{Error::CBOR_NO_INPUT, 0});
+    return;
+  }
+  if (bytes[0] != kInitialByteForEnvelope) {
+    json_out->HandleError(Status{Error::CBOR_INVALID_START_BYTE, 0});
+    return;
+  }
+  CBORTokenizer tokenizer(bytes);
+  if (tokenizer.TokenTag() == CBORTokenTag::ERROR_VALUE) {
+    json_out->HandleError(tokenizer.Status());
+    return;
+  }
+  // We checked for the envelope start byte above, so the tokenizer
+  // must agree here, since it's not an error.
+  assert(tokenizer.TokenTag() == CBORTokenTag::ENVELOPE);
+  tokenizer.EnterEnvelope();
+  if (tokenizer.TokenTag() != CBORTokenTag::MAP_START) {
+    json_out->HandleError(
+        Status{Error::CBOR_MAP_START_EXPECTED, tokenizer.Status().pos});
+    return;
+  }
+  if (!ParseMap(/*stack_depth=*/1, &tokenizer, json_out)) return;
+  if (tokenizer.TokenTag() == CBORTokenTag::DONE) return;
+  if (tokenizer.TokenTag() == CBORTokenTag::ERROR_VALUE) {
+    json_out->HandleError(tokenizer.Status());
+    return;
+  }
+  json_out->HandleError(
+      Status{Error::CBOR_TRAILING_JUNK, tokenizer.Status().pos});
+}
+
+CBORTokenizer::CBORTokenizer(span<uint8_t> bytes) : bytes_(bytes) {
+  ReadNextToken(/*enter_envelope=*/false);
+}
+CBORTokenizer::~CBORTokenizer() {}
+
+CBORTokenTag CBORTokenizer::TokenTag() const { return token_tag_; }
+
+void CBORTokenizer::Next() {
+  if (token_tag_ == CBORTokenTag::ERROR_VALUE || token_tag_ == CBORTokenTag::DONE)
+    return;
+  ReadNextToken(/*enter_envelope=*/false);
+}
+
+void CBORTokenizer::EnterEnvelope() {
+  assert(token_tag_ == CBORTokenTag::ENVELOPE);
+  ReadNextToken(/*enter_envelope=*/true);
+}
+
+Status CBORTokenizer::Status() const { return status_; }
+
+int32_t CBORTokenizer::GetInt32() const {
+  assert(token_tag_ == CBORTokenTag::INT32);
+  // The range checks happen in ::ReadNextToken().
+  return static_cast<uint32_t>(
+      token_start_type_ == MajorType::UNSIGNED
+          ? token_start_internal_value_
+          : -static_cast<int64_t>(token_start_internal_value_) - 1);
+}
+
+double CBORTokenizer::GetDouble() const {
+  assert(token_tag_ == CBORTokenTag::DOUBLE);
+  union {
+    uint64_t from_uint64;
+    double to_double;
+  } reinterpret;
+  reinterpret.from_uint64 = ReadBytesMostSignificantByteFirst<uint64_t>(
+      bytes_.subspan(status_.pos + 1));
+  return reinterpret.to_double;
+}
+
+span<uint8_t> CBORTokenizer::GetString8() const {
+  assert(token_tag_ == CBORTokenTag::STRING8);
+  auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+  return bytes_.subspan(status_.pos + (token_byte_length_ - length), length);
+}
+
+span<uint8_t> CBORTokenizer::GetString16WireRep() const {
+  assert(token_tag_ == CBORTokenTag::STRING16);
+  auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+  return bytes_.subspan(status_.pos + (token_byte_length_ - length), length);
+}
+
+span<uint8_t> CBORTokenizer::GetBinary() const {
+  assert(token_tag_ == CBORTokenTag::BINARY);
+  auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+  return bytes_.subspan(status_.pos + (token_byte_length_ - length), length);
+}
+
+void CBORTokenizer::ReadNextToken(bool enter_envelope) {
+  if (enter_envelope) {
+    status_.pos += kEncodedEnvelopeHeaderSize;
+  } else {
+    status_.pos =
+        status_.pos == Status::npos() ? 0 : status_.pos + token_byte_length_;
+  }
+  status_.error = Error::OK;
+  if (status_.pos >= bytes_.size()) {
+    token_tag_ = CBORTokenTag::DONE;
+    return;
+  }
+  switch (bytes_[status_.pos]) {
+    case kStopByte:
+      SetToken(CBORTokenTag::STOP, 1);
+      return;
+    case kInitialByteIndefiniteLengthMap:
+      SetToken(CBORTokenTag::MAP_START, 1);
+      return;
+    case kInitialByteIndefiniteLengthArray:
+      SetToken(CBORTokenTag::ARRAY_START, 1);
+      return;
+    case kEncodedTrue:
+      SetToken(CBORTokenTag::TRUE_VALUE, 1);
+      return;
+    case kEncodedFalse:
+      SetToken(CBORTokenTag::FALSE_VALUE, 1);
+      return;
+    case kEncodedNull:
+      SetToken(CBORTokenTag::NULL_VALUE, 1);
+      return;
+    case kExpectedConversionToBase64Tag: {  // BINARY
+      int8_t bytes_read =
+          ReadTokenStart(bytes_.subspan(status_.pos + 1), &token_start_type_,
+                         &token_start_internal_value_);
+      int64_t token_byte_length = 1 + bytes_read + token_start_internal_value_;
+      if (-1 == bytes_read || token_start_type_ != MajorType::BYTE_STRING ||
+          status_.pos + token_byte_length > bytes_.size()) {
+        SetError(Error::CBOR_INVALID_BINARY);
+        return;
+      }
+      SetToken(CBORTokenTag::BINARY,
+               static_cast<std::ptrdiff_t>(token_byte_length));
+      return;
+    }
+    case kInitialByteForDouble: {  // DOUBLE
+      if (status_.pos + kEncodedDoubleSize > bytes_.size()) {
+        SetError(Error::CBOR_INVALID_DOUBLE);
+        return;
+      }
+      SetToken(CBORTokenTag::DOUBLE, kEncodedDoubleSize);
+      return;
+    }
+    case kInitialByteForEnvelope: {  // ENVELOPE
+      if (status_.pos + kEncodedEnvelopeHeaderSize > bytes_.size()) {
+        SetError(Error::CBOR_INVALID_ENVELOPE);
+        return;
+      }
+      // The envelope must be a byte string with 32 bit length.
+      if (bytes_[status_.pos + 1] != kInitialByteFor32BitLengthByteString) {
+        SetError(Error::CBOR_INVALID_ENVELOPE);
+        return;
+      }
+      // Read the length of the byte string.
+      token_start_internal_value_ = ReadBytesMostSignificantByteFirst<uint32_t>(
+          bytes_.subspan(status_.pos + 2));
+      // Make sure the payload is contained within the message.
+      if (token_start_internal_value_ + kEncodedEnvelopeHeaderSize +
+              status_.pos >
+          static_cast<std::size_t>(bytes_.size())) {
+        SetError(Error::CBOR_INVALID_ENVELOPE);
+        return;
+      }
+      auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+      SetToken(CBORTokenTag::ENVELOPE,
+               kEncodedEnvelopeHeaderSize + length);
+      return;
+    }
+    default: {
+      span<uint8_t> remainder =
+          bytes_.subspan(status_.pos, bytes_.size() - status_.pos);
+      assert(!remainder.empty());
+      int8_t token_start_length = ReadTokenStart(remainder, &token_start_type_,
+                                                 &token_start_internal_value_);
+      bool success = token_start_length != -1;
+      switch (token_start_type_) {
+        case MajorType::UNSIGNED:  // INT32.
+          if (!success || std::numeric_limits<int32_t>::max() <
+                              token_start_internal_value_) {
+            SetError(Error::CBOR_INVALID_INT32);
+            return;
+          }
+          SetToken(CBORTokenTag::INT32, token_start_length);
+          return;
+        case MajorType::NEGATIVE:  // INT32.
+          if (!success ||
+              std::numeric_limits<int32_t>::min() >
+                  -static_cast<int64_t>(token_start_internal_value_) - 1) {
+            SetError(Error::CBOR_INVALID_INT32);
+            return;
+          }
+          SetToken(CBORTokenTag::INT32, token_start_length);
+          return;
+        case MajorType::STRING: {  // STRING8.
+          if (!success || remainder.size() < static_cast<int64_t>(
+                                                 token_start_internal_value_)) {
+            SetError(Error::CBOR_INVALID_STRING8);
+            return;
+          }
+          auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+          SetToken(CBORTokenTag::STRING8, token_start_length + length);
+          return;
+        }
+        case MajorType::BYTE_STRING: {  // STRING16.
+          if (!success ||
+              remainder.size() <
+                  static_cast<int64_t>(token_start_internal_value_) ||
+              // Must be divisible by 2 since UTF16 is 2 bytes per character.
+              token_start_internal_value_ & 1) {
+            SetError(Error::CBOR_INVALID_STRING16);
+            return;
+          }
+          auto length = static_cast<std::ptrdiff_t>(token_start_internal_value_);
+          SetToken(CBORTokenTag::STRING16, token_start_length + length);
+          return;
+        }
+        case MajorType::ARRAY:
+        case MajorType::MAP:
+        case MajorType::TAG:
+        case MajorType::SIMPLE_VALUE:
+          SetError(Error::CBOR_UNSUPPORTED_VALUE);
+          return;
+      }
+    }
+  }
+}
+
+void CBORTokenizer::SetToken(CBORTokenTag token_tag,
+                             std::ptrdiff_t token_byte_length) {
+  token_tag_ = token_tag;
+  token_byte_length_ = token_byte_length;
+}
+
+void CBORTokenizer::SetError(Error error) {
+  token_tag_ = CBORTokenTag::ERROR_VALUE;
+  status_.error = error;
+}
+
+#if 0
+void DumpCBOR(span<uint8_t> cbor) {
+  std::string indent;
+  CBORTokenizer tokenizer(cbor);
+  while (true) {
+    fprintf(stderr, "%s", indent.c_str());
+    switch (tokenizer.TokenTag()) {
+      case CBORTokenTag::ERROR_VALUE:
+        fprintf(stderr, "ERROR {status.error=%d, status.pos=%ld}\n",
+               tokenizer.Status().error, tokenizer.Status().pos);
+        return;
+      case CBORTokenTag::DONE:
+        fprintf(stderr, "DONE\n");
+        return;
+      case CBORTokenTag::TRUE_VALUE:
+        fprintf(stderr, "TRUE_VALUE\n");
+        break;
+      case CBORTokenTag::FALSE_VALUE:
+        fprintf(stderr, "FALSE_VALUE\n");
+        break;
+      case CBORTokenTag::NULL_VALUE:
+        fprintf(stderr, "NULL_VALUE\n");
+        break;
+      case CBORTokenTag::INT32:
+        fprintf(stderr, "INT32 [%d]\n", tokenizer.GetInt32());
+        break;
+      case CBORTokenTag::DOUBLE:
+        fprintf(stderr, "DOUBLE [%lf]\n", tokenizer.GetDouble());
+        break;
+      case CBORTokenTag::STRING8: {
+        span<uint8_t> v = tokenizer.GetString8();
+        std::string t(v.begin(), v.end());
+        fprintf(stderr, "STRING8 [%s]\n", t.c_str());
+        break;
+      }
+      case CBORTokenTag::STRING16: {
+        span<uint8_t> v = tokenizer.GetString16WireRep();
+        std::string t(v.begin(), v.end());
+        fprintf(stderr, "STRING16 [%s]\n", t.c_str());
+        break;
+      }
+      case CBORTokenTag::BINARY: {
+        span<uint8_t> v = tokenizer.GetBinary();
+        std::string t(v.begin(), v.end());
+        fprintf(stderr, "BINARY [%s]\n", t.c_str());
+        break;
+      }
+      case CBORTokenTag::MAP_START:
+        fprintf(stderr, "MAP_START\n");
+        indent += "  ";
+        break;
+      case CBORTokenTag::ARRAY_START:
+        fprintf(stderr, "ARRAY_START\n");
+        indent += "  ";
+        break;
+      case CBORTokenTag::STOP:
+        fprintf(stderr, "STOP\n");
+        indent.erase(0, 2);
+        break;
+      case CBORTokenTag::ENVELOPE:
+        fprintf(stderr, "ENVELOPE\n");
+        tokenizer.EnterEnvelope();
+        continue;
+    }
+    tokenizer.Next();
+  }
+}
+#endif
+
+
+{% for namespace in config.protocol.namespace %}
+} // namespace {{namespace}}
+{% endfor %}
diff --git a/tools/inspector_protocol/lib/CBOR_h.template b/tools/inspector_protocol/lib/CBOR_h.template
new file mode 100644
index 0000000000..dd637f19e7
--- /dev/null
+++ b/tools/inspector_protocol/lib/CBOR_h.template
@@ -0,0 +1,416 @@
+{# This template is generated by gen_cbor_templates.py. #}
+// Generated by lib/CBOR_h.template.
+
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef {{"_".join(config.protocol.namespace)}}_CBOR_h
+#define {{"_".join(config.protocol.namespace)}}_CBOR_h
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+{% for namespace in config.protocol.namespace %}
+namespace {{namespace}} {
+{% endfor %}
+
+// ===== encoding/status.h =====
+
+// Error codes.
+enum class Error {
+  OK = 0,
+  // JSON parsing errors - json_parser.{h,cc}.
+  JSON_PARSER_UNPROCESSED_INPUT_REMAINS = 0x01,
+  JSON_PARSER_STACK_LIMIT_EXCEEDED = 0x02,
+  JSON_PARSER_NO_INPUT = 0x03,
+  JSON_PARSER_INVALID_TOKEN = 0x04,
+  JSON_PARSER_INVALID_NUMBER = 0x05,
+  JSON_PARSER_INVALID_STRING = 0x06,
+  JSON_PARSER_UNEXPECTED_ARRAY_END = 0x07,
+  JSON_PARSER_COMMA_OR_ARRAY_END_EXPECTED = 0x08,
+  JSON_PARSER_STRING_LITERAL_EXPECTED = 0x09,
+  JSON_PARSER_COLON_EXPECTED = 0x0a,
+  JSON_PARSER_UNEXPECTED_OBJECT_END = 0x0b,
+  JSON_PARSER_COMMA_OR_OBJECT_END_EXPECTED = 0x0c,
+  JSON_PARSER_VALUE_EXPECTED = 0x0d,
+
+  CBOR_INVALID_INT32 = 0x0e,
+  CBOR_INVALID_DOUBLE = 0x0f,
+  CBOR_INVALID_ENVELOPE = 0x10,
+  CBOR_INVALID_STRING8 = 0x11,
+  CBOR_INVALID_STRING16 = 0x12,
+  CBOR_INVALID_BINARY = 0x13,
+  CBOR_UNSUPPORTED_VALUE = 0x14,
+  CBOR_NO_INPUT = 0x15,
+  CBOR_INVALID_START_BYTE = 0x16,
+  CBOR_UNEXPECTED_EOF_EXPECTED_VALUE = 0x17,
+  CBOR_UNEXPECTED_EOF_IN_ARRAY = 0x18,
+  CBOR_UNEXPECTED_EOF_IN_MAP = 0x19,
+  CBOR_INVALID_MAP_KEY = 0x1a,
+  CBOR_STACK_LIMIT_EXCEEDED = 0x1b,
+  CBOR_STRING8_MUST_BE_7BIT = 0x1c,
+  CBOR_TRAILING_JUNK = 0x1d,
+  CBOR_MAP_START_EXPECTED = 0x1e,
+};
+
+// A status value with position that can be copied. The default status
+// is OK. Usually, error status values should come with a valid position.
+struct Status {
+  static constexpr std::ptrdiff_t npos() { return -1; }
+
+  bool ok() const { return error == Error::OK; }
+
+  Error error = Error::OK;
+  std::ptrdiff_t pos = npos();
+  Status(Error error, std::ptrdiff_t pos) : error(error), pos(pos) {}
+  Status() = default;
+};
+
+// ===== encoding/span.h =====
+
+// This template is similar to std::span, which will be included in C++20.  Like
+// std::span it uses ptrdiff_t, which is signed (and thus a bit annoying
+// sometimes when comparing with size_t), but other than this it's much simpler.
+template <typename T>
+class span {
+ public:
+  using index_type = std::ptrdiff_t;
+
+  span() : data_(nullptr), size_(0) {}
+  span(const T* data, index_type size) : data_(data), size_(size) {}
+
+  const T* data() const { return data_; }
+
+  const T* begin() const { return data_; }
+  const T* end() const { return data_ + size_; }
+
+  const T& operator[](index_type idx) const { return data_[idx]; }
+
+  span<T> subspan(index_type offset, index_type count) const {
+    return span(data_ + offset, count);
+  }
+
+  span<T> subspan(index_type offset) const {
+    return span(data_ + offset, size_ - offset);
+  }
+
+  bool empty() const { return size_ == 0; }
+
+  index_type size() const { return size_; }
+  index_type size_bytes() const { return size_ * sizeof(T); }
+
+ private:
+  const T* data_;
+  index_type size_;
+};
+
+// ===== encoding/json_parser_handler.h =====
+
+// Handler interface for JSON parser events. See also json_parser.h.
+class JSONParserHandler {
+ public:
+  virtual ~JSONParserHandler() = default;
+  virtual void HandleObjectBegin() = 0;
+  virtual void HandleObjectEnd() = 0;
+  virtual void HandleArrayBegin() = 0;
+  virtual void HandleArrayEnd() = 0;
+  // TODO(johannes): Support utf8 (requires utf16->utf8 conversion
+  // internally, including handling mismatched surrogate pairs).
+  virtual void HandleString16(std::vector<uint16_t> chars) = 0;
+  virtual void HandleBinary(std::vector<uint8_t> bytes) = 0;
+  virtual void HandleDouble(double value) = 0;
+  virtual void HandleInt32(int32_t value) = 0;
+  virtual void HandleBool(bool value) = 0;
+  virtual void HandleNull() = 0;
+
+  // The parser may send one error even after other events have already
+  // been received. Client code is reponsible to then discard the
+  // already processed events.
+  // |error| must be an eror, as in, |error.is_ok()| can't be true.
+  virtual void HandleError(Status error) = 0;
+};
+
+// ===== encoding/cbor_internals.h =====
+
+namespace cbor {
+enum class MajorType;
+}
+
+namespace cbor_internals {
+
+// Reads the start of a token with definitive size from |bytes|.
+// |type| is the major type as specified in RFC 7049 Section 2.1.
+// |value| is the payload (e.g. for MajorType::UNSIGNED) or is the size
+// (e.g. for BYTE_STRING).
+// If successful, returns the number of bytes read. Otherwise returns -1.
+int8_t ReadTokenStart(span<uint8_t> bytes, cbor::MajorType* type,
+                      uint64_t* value);
+
+// Writes the start of a token with |type|. The |value| may indicate the size,
+// or it may be the payload if the value is an unsigned integer.
+void WriteTokenStart(cbor::MajorType type, uint64_t value,
+                     std::vector<uint8_t>* encoded);
+}  // namespace cbor_internals
+
+// ===== encoding/cbor.h =====
+
+
+namespace cbor {
+
+// The major types from RFC 7049 Section 2.1.
+enum class MajorType {
+  UNSIGNED = 0,
+  NEGATIVE = 1,
+  BYTE_STRING = 2,
+  STRING = 3,
+  ARRAY = 4,
+  MAP = 5,
+  TAG = 6,
+  SIMPLE_VALUE = 7
+};
+
+// Indicates the number of bits the "initial byte" needs to be shifted to the
+// right after applying |kMajorTypeMask| to produce the major type in the
+// lowermost bits.
+static constexpr uint8_t kMajorTypeBitShift = 5u;
+// Mask selecting the low-order 5 bits of the "initial byte", which is where
+// the additional information is encoded.
+static constexpr uint8_t kAdditionalInformationMask = 0x1f;
+// Mask selecting the high-order 3 bits of the "initial byte", which indicates
+// the major type of the encoded value.
+static constexpr uint8_t kMajorTypeMask = 0xe0;
+// Indicates the integer is in the following byte.
+static constexpr uint8_t kAdditionalInformation1Byte = 24u;
+// Indicates the integer is in the next 2 bytes.
+static constexpr uint8_t kAdditionalInformation2Bytes = 25u;
+// Indicates the integer is in the next 4 bytes.
+static constexpr uint8_t kAdditionalInformation4Bytes = 26u;
+// Indicates the integer is in the next 8 bytes.
+static constexpr uint8_t kAdditionalInformation8Bytes = 27u;
+
+// Encodes the initial byte, consisting of the |type| in the first 3 bits
+// followed by 5 bits of |additional_info|.
+constexpr uint8_t EncodeInitialByte(MajorType type, uint8_t additional_info) {
+  return (static_cast<uint8_t>(type) << kMajorTypeBitShift) |
+         (additional_info & kAdditionalInformationMask);
+}
+
+// TAG 24 indicates that what follows is a byte string which is
+// encoded in CBOR format. We use this as a wrapper for
+// maps and arrays, allowing us to skip them, because the
+// byte string carries its size (byte length).
+// https://tools.ietf.org/html/rfc7049#section-2.4.4.1
+static constexpr uint8_t kInitialByteForEnvelope =
+    EncodeInitialByte(MajorType::TAG, 24);
+// The initial byte for a byte string with at most 2^32 bytes
+// of payload. This is used for envelope encoding, even if
+// the byte string is shorter.
+static constexpr uint8_t kInitialByteFor32BitLengthByteString =
+    EncodeInitialByte(MajorType::BYTE_STRING, 26);
+
+// See RFC 7049 Section 2.2.1, indefinite length arrays / maps have additional
+// info = 31.
+static constexpr uint8_t kInitialByteIndefiniteLengthArray =
+    EncodeInitialByte(MajorType::ARRAY, 31);
+static constexpr uint8_t kInitialByteIndefiniteLengthMap =
+    EncodeInitialByte(MajorType::MAP, 31);
+// See RFC 7049 Section 2.3, Table 1; this is used for finishing indefinite
+// length maps / arrays.
+static constexpr uint8_t kStopByte =
+    EncodeInitialByte(MajorType::SIMPLE_VALUE, 31);
+
+}  // namespace cbor
+
+// The binary encoding for the inspector protocol follows the CBOR specification
+// (RFC 7049). Additional constraints:
+// - Only indefinite length maps and arrays are supported.
+// - Maps and arrays are wrapped with an envelope, that is, a
+//   CBOR tag with value 24 followed by a byte string specifying
+//   the byte length of the enclosed map / array. The byte string
+//   must use a 32 bit wide length.
+// - At the top level, a message must be an indefinite length map
+//   wrapped by an envelope.
+// - Maximal size for messages is 2^32 (4 GB).
+// - For scalars, we support only the int32_t range, encoded as
+//   UNSIGNED/NEGATIVE (major types 0 / 1).
+// - UTF16 strings, including with unbalanced surrogate pairs, are encoded
+//   as CBOR BYTE_STRING (major type 2). For such strings, the number of
+//   bytes encoded must be even.
+// - UTF8 strings (major type 3) may only have ASCII characters
+//   (7 bit US-ASCII).
+// - Arbitrary byte arrays, in the inspector protocol called 'binary',
+//   are encoded as BYTE_STRING (major type 2), prefixed with a byte
+//   indicating base64 when rendered as JSON.
+
+// Encodes |value| as |UNSIGNED| (major type 0) iff >= 0, or |NEGATIVE|
+// (major type 1) iff < 0.
+void EncodeInt32(int32_t value, std::vector<uint8_t>* out);
+
+// Encodes a UTF16 string as a BYTE_STRING (major type 2). Each utf16
+// character in |in| is emitted with most significant byte first,
+// appending to |out|.
+void EncodeString16(span<uint16_t> in, std::vector<uint8_t>* out);
+
+// Encodes a UTF8 string |in| as STRING (major type 3).
+void EncodeString8(span<uint8_t> in, std::vector<uint8_t>* out);
+
+// Encodes arbitrary binary data in |in| as a BYTE_STRING (major type 2) with
+// definitive length, prefixed with tag 22 indicating expected conversion to
+// base64 (see RFC 7049, Table 3 and Section 2.4.4.2).
+void EncodeBinary(span<uint8_t> in, std::vector<uint8_t>* out);
+
+// Encodes / decodes a double as Major type 7 (SIMPLE_VALUE),
+// with additional info = 27, followed by 8 bytes in big endian.
+void EncodeDouble(double value, std::vector<uint8_t>* out);
+
+// Some constants for CBOR tokens that only take a single byte on the wire.
+uint8_t EncodeTrue();
+uint8_t EncodeFalse();
+uint8_t EncodeNull();
+uint8_t EncodeIndefiniteLengthArrayStart();
+uint8_t EncodeIndefiniteLengthMapStart();
+uint8_t EncodeStop();
+
+// An envelope indicates the byte length of a wrapped item.
+// We use this for maps and array, which allows the decoder
+// to skip such (nested) values whole sale.
+// It's implemented as a CBOR tag (major type 6) with additional
+// info = 24, followed by a byte string with a 32 bit length value;
+// so the maximal structure that we can wrap is 2^32 bits long.
+// See also: https://tools.ietf.org/html/rfc7049#section-2.4.4.1
+class EnvelopeEncoder {
+ public:
+  // Emits the envelope start bytes and records the position for the
+  // byte size in |byte_size_pos_|. Also emits empty bytes for the
+  // byte sisze so that encoding can continue.
+  void EncodeStart(std::vector<uint8_t>* out);
+  // This records the current size in |out| at position byte_size_pos_.
+  // Returns true iff successful.
+  bool EncodeStop(std::vector<uint8_t>* out);
+
+ private:
+  std::size_t byte_size_pos_ = 0;
+};
+
+// This can be used to convert from JSON to CBOR, by passing the
+// return value to the routines in json_parser.h.  The handler will encode into
+// |out|, and iff an error occurs it will set |status| to an error and clear
+// |out|. Otherwise, |status.ok()| will be |true|.
+std::unique_ptr<JSONParserHandler> NewJSONToCBOREncoder(
+    std::vector<uint8_t>* out, Status* status);
+
+// Parses a CBOR encoded message from |bytes|, sending JSON events to
+// |json_out|. If an error occurs, sends |out->HandleError|, and parsing stops.
+// The client is responsible for discarding the already received information in
+// that case.
+void ParseCBOR(span<uint8_t> bytes, JSONParserHandler* json_out);
+
+// Tags for the tokens within a CBOR message that CBORStream understands.
+// Note that this is not the same terminology as the CBOR spec (RFC 7049),
+// but rather, our adaptation. For instance, we lump unsigned and signed
+// major type into INT32 here (and disallow values outside the int32_t range).
+enum class CBORTokenTag {
+  // Encountered an error in the structure of the message. Consult
+  // status() for details.
+  ERROR_VALUE,
+  // Booleans and NULL.
+  TRUE_VALUE,
+  FALSE_VALUE,
+  NULL_VALUE,
+  // An int32_t (signed 32 bit integer).
+  INT32,
+  // A double (64 bit floating point).
+  DOUBLE,
+  // A UTF8 string.
+  STRING8,
+  // A UTF16 string.
+  STRING16,
+  // A binary string.
+  BINARY,
+  // Starts an indefinite length map; after the map start we expect
+  // alternating keys and values, followed by STOP.
+  MAP_START,
+  // Starts an indefinite length array; after the array start we
+  // expect values, followed by STOP.
+  ARRAY_START,
+  // Ends a map or an array.
+  STOP,
+  // An envelope indicator, wrapping a map or array.
+  // Internally this carries the byte length of the wrapped
+  // map or array. While CBORTokenizer::Next() will read / skip the entire
+  // envelope, CBORTokenizer::EnterEnvelope() reads the tokens
+  // inside of it.
+  ENVELOPE,
+  // We've reached the end there is nothing else to read.
+  DONE,
+};
+
+// CBORTokenizer segments a CBOR message, presenting the tokens therein as
+// numbers, strings, etc. This is not a complete CBOR parser, but makes it much
+// easier to implement one (e.g. ParseCBOR, above). It can also be used to parse
+// messages partially.
+class CBORTokenizer {
+ public:
+  explicit CBORTokenizer(span<uint8_t> bytes);
+  ~CBORTokenizer();
+
+  // Identifies the current token that we're looking at,
+  // or ERROR_VALUE (in which ase ::Status() has details)
+  // or DONE (if we're past the last token).
+  CBORTokenTag TokenTag() const;
+
+  // Advances to the next token.
+  void Next();
+  // Can only be called if TokenTag() == CBORTokenTag::ENVELOPE.
+  // While Next() would skip past the entire envelope / what it's
+  // wrapping, EnterEnvelope positions the cursor inside of the envelope,
+  // letting the client explore the nested structure.
+  void EnterEnvelope();
+
+  // If TokenTag() is CBORTokenTag::ERROR_VALUE, then Status().error describes
+  // the error more precisely; otherwise it'll be set to Error::OK.
+  // In either case, Status().pos is the current position.
+  struct Status Status() const;
+
+  // The following methods retrieve the token values. They can only
+  // be called if TokenTag() matches.
+
+  // To be called only if ::TokenTag() == CBORTokenTag::INT32.
+  int32_t GetInt32() const;
+
+  // To be called only if ::TokenTag() == CBORTokenTag::DOUBLE.
+  double GetDouble() const;
+
+  // To be called only if ::TokenTag() == CBORTokenTag::STRING8.
+  span<uint8_t> GetString8() const;
+
+  // Wire representation for STRING16 is low byte first (little endian).
+  // To be called only if ::TokenTag() == CBORTokenTag::STRING16.
+  span<uint8_t> GetString16WireRep() const;
+
+  // To be called only if ::TokenTag() == CBORTokenTag::BINARY.
+  span<uint8_t> GetBinary() const;
+
+ private:
+  void ReadNextToken(bool enter_envelope);
+  void SetToken(CBORTokenTag token, std::ptrdiff_t token_byte_length);
+  void SetError(Error error);
+
+  span<uint8_t> bytes_;
+  CBORTokenTag token_tag_;
+  struct Status status_;
+  std::ptrdiff_t token_byte_length_;
+  cbor::MajorType token_start_type_;
+  uint64_t token_start_internal_value_;
+};
+
+void DumpCBOR(span<uint8_t> cbor);
+
+
+{% for namespace in config.protocol.namespace %}
+} // namespace {{namespace}}
+{% endfor %}
+#endif // !defined({{"_".join(config.protocol.namespace)}}_CBOR_h)
diff --git a/tools/inspector_protocol/lib/DispatcherBase_cpp.template b/tools/inspector_protocol/lib/DispatcherBase_cpp.template
index cecef743bf..11843f4330 100644
--- a/tools/inspector_protocol/lib/DispatcherBase_cpp.template
+++ b/tools/inspector_protocol/lib/DispatcherBase_cpp.template
@@ -1,3 +1,5 @@
+// This file is generated by DispatcherBase_cpp.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -68,10 +70,11 @@ DispatcherBase::WeakPtr::~WeakPtr()
         m_dispatcher->m_weakPtrs.erase(this);
 }
 
-DispatcherBase::Callback::Callback(std::unique_ptr<DispatcherBase::WeakPtr> backendImpl, int callId, int callbackId)
+DispatcherBase::Callback::Callback(std::unique_ptr<DispatcherBase::WeakPtr> backendImpl, int callId, const String& method, const ProtocolMessage& message)
     : m_backendImpl(std::move(backendImpl))
     , m_callId(callId)
-    , m_callbackId(callbackId) { }
+    , m_method(method)
+    , m_message(message) { }
 
 DispatcherBase::Callback::~Callback() = default;
 
@@ -92,32 +95,18 @@ void DispatcherBase::Callback::fallThroughIfActive()
 {
     if (!m_backendImpl || !m_backendImpl->get())
         return;
-    m_backendImpl->get()->markFallThrough(m_callbackId);
+    m_backendImpl->get()->channel()->fallThrough(m_callId, m_method, m_message);
     m_backendImpl = nullptr;
 }
 
 DispatcherBase::DispatcherBase(FrontendChannel* frontendChannel)
-    : m_frontendChannel(frontendChannel)
-    , m_lastCallbackId(0)
-    , m_lastCallbackFallThrough(false) { }
+    : m_frontendChannel(frontendChannel) { }
 
 DispatcherBase::~DispatcherBase()
 {
     clearFrontend();
 }
 
-int DispatcherBase::nextCallbackId()
-{
-    m_lastCallbackFallThrough = false;
-    return ++m_lastCallbackId;
-}
-
-void DispatcherBase::markFallThrough(int callbackId)
-{
-    DCHECK(callbackId == m_lastCallbackId);
-    m_lastCallbackFallThrough = true;
-}
-
 void DispatcherBase::sendResponse(int callId, const DispatchResponse& response, std::unique_ptr<protocol::DictionaryValue> result)
 {
     if (!m_frontendChannel)
@@ -153,18 +142,14 @@ public:
         return std::unique_ptr<ProtocolError>(new ProtocolError(code, errorMessage));
     }
 
-    String serialize() override
+    String serializeToJSON() override
     {
-        std::unique_ptr<protocol::DictionaryValue> error = DictionaryValue::create();
-        error->setInteger("code", m_code);
-        error->setString("message", m_errorMessage);
-        if (m_data.length())
-            error->setString("data", m_data);
-        std::unique_ptr<protocol::DictionaryValue> message = DictionaryValue::create();
-        message->setObject("error", std::move(error));
-        if (m_hasCallId)
-            message->setInteger("id", m_callId);
-        return message->serialize();
+        return serialize()->serializeToJSON();
+    }
+
+    std::vector<uint8_t> serializeToBinary() override
+    {
+        return serialize()->serializeToBinary();
     }
 
     ~ProtocolError() override {}
@@ -176,6 +161,19 @@ private:
     {
     }
 
+    std::unique_ptr<DictionaryValue> serialize() {
+        std::unique_ptr<protocol::DictionaryValue> error = DictionaryValue::create();
+        error->setInteger("code", m_code);
+        error->setString("message", m_errorMessage);
+        if (m_data.length())
+            error->setString("data", m_data);
+        std::unique_ptr<protocol::DictionaryValue> message = DictionaryValue::create();
+        message->setObject("error", std::move(error));
+        if (m_hasCallId)
+            message->setInteger("id", m_callId);
+        return message;
+    }
+
     DispatchResponse::ErrorCode m_code;
     String m_errorMessage;
     String m_data;
@@ -218,100 +216,87 @@ std::unique_ptr<DispatcherBase::WeakPtr> DispatcherBase::weakPtr()
 }
 
 UberDispatcher::UberDispatcher(FrontendChannel* frontendChannel)
-    : m_frontendChannel(frontendChannel)
-    , m_fallThroughForNotFound(false) { }
-
-void UberDispatcher::setFallThroughForNotFound(bool fallThroughForNotFound)
-{
-    m_fallThroughForNotFound = fallThroughForNotFound;
-}
+    : m_frontendChannel(frontendChannel) { }
 
 void UberDispatcher::registerBackend(const String& name, std::unique_ptr<protocol::DispatcherBase> dispatcher)
 {
     m_dispatchers[name] = std::move(dispatcher);
 }
 
-void UberDispatcher::setupRedirects(const HashMap<String, String>& redirects)
+void UberDispatcher::setupRedirects(const std::unordered_map<String, String>& redirects)
 {
     for (const auto& pair : redirects)
         m_redirects[pair.first] = pair.second;
 }
 
-DispatchResponse::Status UberDispatcher::dispatch(std::unique_ptr<Value> parsedMessage, int* outCallId, String* outMethod)
-{
+bool UberDispatcher::parseCommand(Value* parsedMessage, int* outCallId, String* outMethod) {
     if (!parsedMessage) {
         reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kParseError, "Message must be a valid JSON");
-        return DispatchResponse::kError;
+        return false;
     }
-    std::unique_ptr<protocol::DictionaryValue> messageObject = DictionaryValue::cast(std::move(parsedMessage));
+    protocol::DictionaryValue* messageObject = DictionaryValue::cast(parsedMessage);
     if (!messageObject) {
         reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must be an object");
-        return DispatchResponse::kError;
+        return false;
     }
 
     int callId = 0;
     protocol::Value* callIdValue = messageObject->get("id");
     bool success = callIdValue && callIdValue->asInteger(&callId);
-    if (outCallId)
-        *outCallId = callId;
     if (!success) {
         reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must have integer 'id' property");
-        return DispatchResponse::kError;
+        return false;
     }
+    if (outCallId)
+      *outCallId = callId;
 
     protocol::Value* methodValue = messageObject->get("method");
     String method;
     success = methodValue && methodValue->asString(&method);
-    if (outMethod)
-        *outMethod = method;
     if (!success) {
         reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kInvalidRequest, "Message must have string 'method' property", nullptr);
-        return DispatchResponse::kError;
+        return false;
     }
+    if (outMethod)
+      *outMethod = method;
+    return true;
+}
 
-    HashMap<String, String>::iterator redirectIt = m_redirects.find(method);
-    if (redirectIt != m_redirects.end())
-        method = redirectIt->second;
-
+protocol::DispatcherBase* UberDispatcher::findDispatcher(const String& method) {
     size_t dotIndex = StringUtil::find(method, ".");
-    if (dotIndex == StringUtil::kNotFound) {
-        if (m_fallThroughForNotFound)
-            return DispatchResponse::kFallThrough;
-        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return DispatchResponse::kError;
-    }
+    if (dotIndex == StringUtil::kNotFound)
+        return nullptr;
     String domain = StringUtil::substring(method, 0, dotIndex);
     auto it = m_dispatchers.find(domain);
-    if (it == m_dispatchers.end()) {
-        if (m_fallThroughForNotFound)
-            return DispatchResponse::kFallThrough;
-        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return DispatchResponse::kError;
-    }
-    return it->second->dispatch(callId, method, std::move(messageObject));
+    if (it == m_dispatchers.end())
+        return nullptr;
+    if (!it->second->canDispatch(method))
+        return nullptr;
+    return it->second.get();
 }
 
-bool UberDispatcher::getCommandName(const String& message, String* method, std::unique_ptr<protocol::DictionaryValue>* parsedMessage)
+bool UberDispatcher::canDispatch(const String& in_method)
 {
-    std::unique_ptr<protocol::Value> value = StringUtil::parseJSON(message);
-    if (!value) {
-        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kParseError, "Message must be a valid JSON");
-        return false;
-   }
-
-    protocol::DictionaryValue* object = DictionaryValue::cast(value.get());
-    if (!object) {
-        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must be an object");
-        return false;
-    }
+    String method = in_method;
+    auto redirectIt = m_redirects.find(method);
+    if (redirectIt != m_redirects.end())
+        method = redirectIt->second;
+    return !!findDispatcher(method);
+}
 
-    if (!object->getString("method", method)) {
-        reportProtocolErrorTo(m_frontendChannel, DispatchResponse::kInvalidRequest, "Message must have string 'method' property");
-        return false;
+void UberDispatcher::dispatch(int callId, const String& in_method, std::unique_ptr<Value> parsedMessage, const ProtocolMessage& rawMessage)
+{
+    String method = in_method;
+    auto redirectIt = m_redirects.find(method);
+    if (redirectIt != m_redirects.end())
+        method = redirectIt->second;
+    protocol::DispatcherBase* dispatcher = findDispatcher(method);
+    if (!dispatcher) {
+        reportProtocolErrorTo(m_frontendChannel, callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
+        return;
     }
-
-    parsedMessage->reset(DictionaryValue::cast(value.release()));
-    return true;
+    std::unique_ptr<protocol::DictionaryValue> messageObject = DictionaryValue::cast(std::move(parsedMessage));
+    dispatcher->dispatch(callId, method, rawMessage, std::move(messageObject));
 }
 
 UberDispatcher::~UberDispatcher() = default;
@@ -328,18 +313,32 @@ std::unique_ptr<InternalResponse> InternalResponse::createNotification(const Str
     return std::unique_ptr<InternalResponse>(new InternalResponse(0, notification, std::move(params)));
 }
 
-String InternalResponse::serialize()
+String InternalResponse::serializeToJSON()
+{
+    std::unique_ptr<DictionaryValue> result = DictionaryValue::create();
+    std::unique_ptr<Serializable> params(m_params ? std::move(m_params) : DictionaryValue::create());
+    if (m_notification.length()) {
+        result->setString("method", m_notification);
+        result->setValue("params", SerializedValue::fromJSON(params->serializeToJSON()));
+    } else {
+        result->setInteger("id", m_callId);
+        result->setValue("result", SerializedValue::fromJSON(params->serializeToJSON()));
+    }
+    return result->serializeToJSON();
+}
+
+std::vector<uint8_t> InternalResponse::serializeToBinary()
 {
     std::unique_ptr<DictionaryValue> result = DictionaryValue::create();
     std::unique_ptr<Serializable> params(m_params ? std::move(m_params) : DictionaryValue::create());
     if (m_notification.length()) {
         result->setString("method", m_notification);
-        result->setValue("params", SerializedValue::create(params->serialize()));
+        result->setValue("params", SerializedValue::fromBinary(params->serializeToBinary()));
     } else {
         result->setInteger("id", m_callId);
-        result->setValue("result", SerializedValue::create(params->serialize()));
+        result->setValue("result", SerializedValue::fromBinary(params->serializeToBinary()));
     }
-    return result->serialize();
+    return result->serializeToBinary();
 }
 
 InternalResponse::InternalResponse(int callId, const String& notification, std::unique_ptr<Serializable> params)
diff --git a/tools/inspector_protocol/lib/DispatcherBase_h.template b/tools/inspector_protocol/lib/DispatcherBase_h.template
index d70a4afe71..7d859c4f27 100644
--- a/tools/inspector_protocol/lib/DispatcherBase_h.template
+++ b/tools/inspector_protocol/lib/DispatcherBase_h.template
@@ -1,3 +1,5 @@
+// This file is generated by DispatcherBase_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -5,9 +7,8 @@
 #ifndef {{"_".join(config.protocol.namespace)}}_DispatcherBase_h
 #define {{"_".join(config.protocol.namespace)}}_DispatcherBase_h
 
-//#include "Collections.h"
-//#include "ErrorSupport.h"
 //#include "Forward.h"
+//#include "ErrorSupport.h"
 //#include "Values.h"
 
 {% for namespace in config.protocol.namespace %}
@@ -22,7 +23,6 @@ public:
         kSuccess = 0,
         kError = 1,
         kFallThrough = 2,
-        kAsync = 3
     };
 
     enum ErrorCode {
@@ -68,7 +68,7 @@ public:
 
     class {{config.lib.export_macro}} Callback {
     public:
-        Callback(std::unique_ptr<WeakPtr> backendImpl, int callId, int callbackId);
+        Callback(std::unique_ptr<WeakPtr> backendImpl, int callId, const String& method, const ProtocolMessage& message);
         virtual ~Callback();
         void dispose();
 
@@ -79,13 +79,16 @@ public:
     private:
         std::unique_ptr<WeakPtr> m_backendImpl;
         int m_callId;
-        int m_callbackId;
+        String m_method;
+        ProtocolMessage m_message;
     };
 
     explicit DispatcherBase(FrontendChannel*);
     virtual ~DispatcherBase();
 
-    virtual DispatchResponse::Status dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) = 0;
+    virtual bool canDispatch(const String& method) = 0;
+    virtual void dispatch(int callId, const String& method, const ProtocolMessage& rawMessage, std::unique_ptr<protocol::DictionaryValue> messageObject) = 0;
+    FrontendChannel* channel() { return m_frontendChannel; }
 
     void sendResponse(int callId, const DispatchResponse&, std::unique_ptr<protocol::DictionaryValue> result);
     void sendResponse(int callId, const DispatchResponse&);
@@ -95,15 +98,9 @@ public:
 
     std::unique_ptr<WeakPtr> weakPtr();
 
-    int nextCallbackId();
-    void markFallThrough(int callbackId);
-    bool lastCallbackFallThrough() { return m_lastCallbackFallThrough; }
-
 private:
     FrontendChannel* m_frontendChannel;
-    protocol::HashSet<WeakPtr*> m_weakPtrs;
-    int m_lastCallbackId;
-    bool m_lastCallbackFallThrough;
+    std::unordered_set<WeakPtr*> m_weakPtrs;
 };
 
 class {{config.lib.export_macro}} UberDispatcher {
@@ -111,19 +108,18 @@ class {{config.lib.export_macro}} UberDispatcher {
 public:
     explicit UberDispatcher(FrontendChannel*);
     void registerBackend(const String& name, std::unique_ptr<protocol::DispatcherBase>);
-    void setupRedirects(const HashMap<String, String>&);
-    DispatchResponse::Status dispatch(std::unique_ptr<Value> message, int* callId = nullptr, String* method = nullptr);
+    void setupRedirects(const std::unordered_map<String, String>&);
+    bool parseCommand(Value* message, int* callId, String* method);
+    bool canDispatch(const String& method);
+    void dispatch(int callId, const String& method, std::unique_ptr<Value> message, const ProtocolMessage& rawMessage);
     FrontendChannel* channel() { return m_frontendChannel; }
-    bool fallThroughForNotFound() { return m_fallThroughForNotFound; }
-    void setFallThroughForNotFound(bool);
-    bool getCommandName(const String& message, String* method, std::unique_ptr<protocol::DictionaryValue>* parsedMessage);
     virtual ~UberDispatcher();
 
 private:
+    protocol::DispatcherBase* findDispatcher(const String& method);
     FrontendChannel* m_frontendChannel;
-    bool m_fallThroughForNotFound;
-    HashMap<String, String> m_redirects;
-    protocol::HashMap<String, std::unique_ptr<protocol::DispatcherBase>> m_dispatchers;
+    std::unordered_map<String, String> m_redirects;
+    std::unordered_map<String, std::unique_ptr<protocol::DispatcherBase>> m_dispatchers;
 };
 
 class InternalResponse : public Serializable {
@@ -132,7 +128,8 @@ public:
     static std::unique_ptr<InternalResponse> createResponse(int callId, std::unique_ptr<Serializable> params);
     static std::unique_ptr<InternalResponse> createNotification(const String& notification, std::unique_ptr<Serializable> params = nullptr);
 
-    String serialize() override;
+    String serializeToJSON() override;
+    std::vector<uint8_t> serializeToBinary() override;
 
     ~InternalResponse() override {}
 
@@ -146,24 +143,36 @@ private:
 
 class InternalRawNotification : public Serializable {
 public:
-    static std::unique_ptr<InternalRawNotification> create(const String& notification)
+    static std::unique_ptr<InternalRawNotification> fromJSON(String notification)
+    {
+        return std::unique_ptr<InternalRawNotification>(new InternalRawNotification(std::move(notification)));
+    }
+
+    static std::unique_ptr<InternalRawNotification> fromBinary(std::vector<uint8_t> notification)
     {
-        return std::unique_ptr<InternalRawNotification>(new InternalRawNotification(notification));
+        return std::unique_ptr<InternalRawNotification>(new InternalRawNotification(std::move(notification)));
     }
+
     ~InternalRawNotification() override {}
 
-    String serialize() override
+    String serializeToJSON() override
+    {
+        return std::move(m_jsonNotification);
+    }
+
+    std::vector<uint8_t> serializeToBinary() override
     {
-        return m_notification;
+        return std::move(m_binaryNotification);
     }
 
 private:
-  explicit InternalRawNotification(const String& notification)
-    : m_notification(notification)
-  {
-  }
+  explicit InternalRawNotification(String notification)
+    : m_jsonNotification(std::move(notification)) { }
+  explicit InternalRawNotification(std::vector<uint8_t> notification)
+    : m_binaryNotification(std::move(notification)) { }
 
-  String m_notification;
+  String m_jsonNotification;
+  std::vector<uint8_t> m_binaryNotification;
 };
 
 {% for namespace in config.protocol.namespace %}
diff --git a/tools/inspector_protocol/lib/ErrorSupport_cpp.template b/tools/inspector_protocol/lib/ErrorSupport_cpp.template
index 7b858b8dc4..a5c2a79bbd 100644
--- a/tools/inspector_protocol/lib/ErrorSupport_cpp.template
+++ b/tools/inspector_protocol/lib/ErrorSupport_cpp.template
@@ -1,3 +1,5 @@
+// This file is generated by ErrorSupport_cpp.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
diff --git a/tools/inspector_protocol/lib/ErrorSupport_h.template b/tools/inspector_protocol/lib/ErrorSupport_h.template
index 083f2a5eb0..f317a3cfb4 100644
--- a/tools/inspector_protocol/lib/ErrorSupport_h.template
+++ b/tools/inspector_protocol/lib/ErrorSupport_h.template
@@ -1,3 +1,5 @@
+// This file is generated by ErrorSupport_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -5,7 +7,7 @@
 #ifndef {{"_".join(config.protocol.namespace)}}_ErrorSupport_h
 #define {{"_".join(config.protocol.namespace)}}_ErrorSupport_h
 
-//#include "Forward.h"
+#include {{format_include(config.protocol.package, "Forward")}}
 
 {% for namespace in config.protocol.namespace %}
 namespace {{namespace}} {
diff --git a/tools/inspector_protocol/lib/Forward_h.template b/tools/inspector_protocol/lib/Forward_h.template
index 34d1c0d3e9..ff5e685863 100644
--- a/tools/inspector_protocol/lib/Forward_h.template
+++ b/tools/inspector_protocol/lib/Forward_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Forward_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -10,7 +12,11 @@
 {% endif %}
 #include {{format_include(config.lib.string_header)}}
 
+#include <cstddef>
+#include <memory>
 #include <vector>
+#include <unordered_map>
+#include <unordered_set>
 
 {% for namespace in config.protocol.namespace %}
 namespace {{namespace}} {
diff --git a/tools/inspector_protocol/lib/FrontendChannel_h.template b/tools/inspector_protocol/lib/FrontendChannel_h.template
index 0454978b0c..df104debad 100644
--- a/tools/inspector_protocol/lib/FrontendChannel_h.template
+++ b/tools/inspector_protocol/lib/FrontendChannel_h.template
@@ -1,3 +1,5 @@
+// This file is generated by FrontendChannel_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -11,7 +13,14 @@ namespace {{namespace}} {
 
 class {{config.lib.export_macro}} Serializable {
 public:
-    virtual String serialize() = 0;
+    ProtocolMessage serialize(bool binary) {
+      if (binary)
+        return StringUtil::binaryToMessage(serializeToBinary());
+      else
+        return StringUtil::jsonToMessage(serializeToJSON());
+    }
+    virtual String serializeToJSON() = 0;
+    virtual std::vector<uint8_t> serializeToBinary() = 0;
     virtual ~Serializable() = default;
 };
 
@@ -20,6 +29,7 @@ public:
     virtual ~FrontendChannel() { }
     virtual void sendProtocolResponse(int callId, std::unique_ptr<Serializable> message) = 0;
     virtual void sendProtocolNotification(std::unique_ptr<Serializable> message) = 0;
+    virtual void fallThrough(int callId, const String& method, const ProtocolMessage& message) = 0;
     virtual void flushProtocolNotifications() = 0;
 };
 
diff --git a/tools/inspector_protocol/lib/Maybe_h.template b/tools/inspector_protocol/lib/Maybe_h.template
index 71593acd0e..22cfac6b24 100644
--- a/tools/inspector_protocol/lib/Maybe_h.template
+++ b/tools/inspector_protocol/lib/Maybe_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Maybe_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -5,6 +7,41 @@
 #ifndef {{"_".join(config.protocol.namespace)}}_Maybe_h
 #define {{"_".join(config.protocol.namespace)}}_Maybe_h
 
+// This macro allows to test for the version of the GNU C++ compiler.
+// Note that this also applies to compilers that masquerade as GCC,
+// for example clang and the Intel C++ compiler for Linux.
+// Use like:
+//  #if IP_GNUC_PREREQ(4, 3, 1)
+//   ...
+//  #endif
+#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__)
+#define IP_GNUC_PREREQ(major, minor, patchlevel)                      \
+  ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= \
+   ((major)*10000 + (minor)*100 + (patchlevel)))
+#elif defined(__GNUC__) && defined(__GNUC_MINOR__)
+#define IP_GNUC_PREREQ(major, minor, patchlevel) \
+  ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >=  \
+   ((major)*10000 + (minor)*100 + (patchlevel)))
+#else
+#define IP_GNUC_PREREQ(major, minor, patchlevel) 0
+#endif
+
+#if defined(__mips64)
+#define IP_TARGET_ARCH_MIPS64 1
+#elif defined(__MIPSEB__) || defined(__MIPSEL__)
+#define IP_TARGET_ARCH_MIPS 1
+#endif
+
+// Allowing the use of noexcept by removing the keyword on older compilers that
+// do not support adding noexcept to default members.
+#if ((IP_GNUC_PREREQ(4, 9, 0) && !defined(IP_TARGET_ARCH_MIPS) && \
+      !defined(IP_TARGET_ARCH_MIPS64)) ||                         \
+     (defined(__clang__) && __cplusplus > 201300L))
+#define IP_NOEXCEPT noexcept
+#else
+#define IP_NOEXCEPT
+#endif
+
 //#include "Forward.h"
 
 {% for namespace in config.protocol.namespace %}
@@ -16,7 +53,7 @@ class Maybe {
 public:
     Maybe() : m_value() { }
     Maybe(std::unique_ptr<T> value) : m_value(std::move(value)) { }
-    Maybe(Maybe&& other) : m_value(std::move(other.m_value)) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : m_value(std::move(other.m_value)) {}
     void operator=(std::unique_ptr<T> value) { m_value = std::move(value); }
     T* fromJust() const { DCHECK(m_value); return m_value.get(); }
     T* fromMaybe(T* defaultValue) const { return m_value ? m_value.get() : defaultValue; }
@@ -31,7 +68,9 @@ class MaybeBase {
 public:
     MaybeBase() : m_isJust(false) { }
     MaybeBase(T value) : m_isJust(true), m_value(value) { }
-    MaybeBase(MaybeBase&& other) : m_isJust(other.m_isJust), m_value(std::move(other.m_value)) { }
+    MaybeBase(MaybeBase&& other) IP_NOEXCEPT
+        : m_isJust(other.m_isJust),
+          m_value(std::move(other.m_value)) {}
     void operator=(T value) { m_value = value; m_isJust = true; }
     T fromJust() const { DCHECK(m_isJust); return m_value; }
     T fromMaybe(const T& defaultValue) const { return m_isJust ? m_value : defaultValue; }
@@ -46,27 +85,27 @@ protected:
 template<>
 class Maybe<bool> : public MaybeBase<bool> {
 public:
-    Maybe() { }
+    Maybe() { m_value = false; }
     Maybe(bool value) : MaybeBase(value) { }
-    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
 };
 
 template<>
 class Maybe<int> : public MaybeBase<int> {
 public:
-    Maybe() { }
+    Maybe() { m_value = 0; }
     Maybe(int value) : MaybeBase(value) { }
-    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
 };
 
 template<>
 class Maybe<double> : public MaybeBase<double> {
 public:
-    Maybe() { }
+    Maybe() { m_value = 0; }
     Maybe(double value) : MaybeBase(value) { }
-    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
 };
 
@@ -75,7 +114,16 @@ class Maybe<String> : public MaybeBase<String> {
 public:
     Maybe() { }
     Maybe(const String& value) : MaybeBase(value) { }
-    Maybe(Maybe&& other) : MaybeBase(std::move(other)) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
+    using MaybeBase::operator=;
+};
+
+template<>
+class Maybe<Binary> : public MaybeBase<Binary> {
+public:
+    Maybe() { }
+    Maybe(Binary value) : MaybeBase(value) { }
+    Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
 };
 
@@ -83,4 +131,9 @@ public:
 } // namespace {{namespace}}
 {% endfor %}
 
+#undef IP_GNUC_PREREQ
+#undef IP_TARGET_ARCH_MIPS64
+#undef IP_TARGET_ARCH_MIPS
+#undef IP_NOEXCEPT
+
 #endif // !defined({{"_".join(config.protocol.namespace)}}_Maybe_h)
diff --git a/tools/inspector_protocol/lib/Object_cpp.template b/tools/inspector_protocol/lib/Object_cpp.template
index 91723a71e2..1640a11127 100644
--- a/tools/inspector_protocol/lib/Object_cpp.template
+++ b/tools/inspector_protocol/lib/Object_cpp.template
@@ -1,3 +1,5 @@
+// This file is generated by Object_cpp.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
diff --git a/tools/inspector_protocol/lib/Object_h.template b/tools/inspector_protocol/lib/Object_h.template
index f6ffc57659..ec953d0d48 100644
--- a/tools/inspector_protocol/lib/Object_h.template
+++ b/tools/inspector_protocol/lib/Object_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Object_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -16,12 +18,12 @@ namespace {{namespace}} {
 class {{config.lib.export_macro}} Object {
 public:
     static std::unique_ptr<Object> fromValue(protocol::Value*, ErrorSupport*);
+    explicit Object(std::unique_ptr<protocol::DictionaryValue>);
     ~Object();
 
     std::unique_ptr<protocol::DictionaryValue> toValue() const;
     std::unique_ptr<Object> clone() const;
 private:
-    explicit Object(std::unique_ptr<protocol::DictionaryValue>);
     std::unique_ptr<protocol::DictionaryValue> m_object;
 };
 
diff --git a/tools/inspector_protocol/lib/Parser_cpp.template b/tools/inspector_protocol/lib/Parser_cpp.template
index f3dde5ac21..ea7ecc5a1a 100644
--- a/tools/inspector_protocol/lib/Parser_cpp.template
+++ b/tools/inspector_protocol/lib/Parser_cpp.template
@@ -1,3 +1,5 @@
+// This file is generated by Parser_cpp.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -425,9 +427,8 @@ std::unique_ptr<Value> buildValue(const Char* start, const Char* end, const Char
         double value = charactersToDouble(tokenStart, tokenEnd - tokenStart, &ok);
         if (!ok)
             return nullptr;
-        int number = static_cast<int>(value);
-        if (number == value)
-            result = FundamentalValue::create(number);
+        if (value >= INT_MIN && value <= INT_MAX && static_cast<int>(value) == value)
+            result = FundamentalValue::create(static_cast<int>(value));
         else
             result = FundamentalValue::create(value);
         break;
diff --git a/tools/inspector_protocol/lib/Parser_h.template b/tools/inspector_protocol/lib/Parser_h.template
index 8397d3f5d6..1832c2e972 100644
--- a/tools/inspector_protocol/lib/Parser_h.template
+++ b/tools/inspector_protocol/lib/Parser_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Parser_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
diff --git a/tools/inspector_protocol/lib/Protocol_cpp.template b/tools/inspector_protocol/lib/Protocol_cpp.template
index 901656373a..88303a27ab 100644
--- a/tools/inspector_protocol/lib/Protocol_cpp.template
+++ b/tools/inspector_protocol/lib/Protocol_cpp.template
@@ -1,4 +1,4 @@
-// This file is generated.
+// This file is generated by Protocol_cpp.template.
 
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
@@ -7,6 +7,6 @@
 #include {{format_include(config.protocol.package, "Protocol")}}
 
 #include <algorithm>
+#include <climits>
 #include <cmath>
-
 #include <cstring>
diff --git a/tools/inspector_protocol/lib/ValueConversions_h.template b/tools/inspector_protocol/lib/ValueConversions_h.template
index 4d64ec9091..2ee5b72454 100644
--- a/tools/inspector_protocol/lib/ValueConversions_h.template
+++ b/tools/inspector_protocol/lib/ValueConversions_h.template
@@ -1,3 +1,5 @@
+// This file is generated by ValueConversions_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -100,6 +102,33 @@ struct ValueConversions<String> {
 };
 
 template<>
+struct ValueConversions<Binary> {
+    static Binary fromValue(protocol::Value* value, ErrorSupport* errors)
+    {
+        if (!value ||
+            (value->type() != Value::TypeBinary && value->type() != Value::TypeString)) {
+            errors->addError("Either string base64 or binary value expected");
+            return Binary();
+        }
+        Binary binary;
+        if (value->asBinary(&binary))
+            return binary;
+        String result;
+        value->asString(&result);
+        bool success;
+        Binary out = Binary::fromBase64(result, &success);
+        if (!success)
+          errors->addError("base64 decoding error");
+        return out;
+    }
+
+    static std::unique_ptr<protocol::Value> toValue(const Binary& value)
+    {
+        return BinaryValue::create(value);
+    }
+};
+
+template<>
 struct ValueConversions<Value> {
     static std::unique_ptr<Value> fromValue(protocol::Value* value, ErrorSupport* errors)
     {
diff --git a/tools/inspector_protocol/lib/Values_cpp.template b/tools/inspector_protocol/lib/Values_cpp.template
index b9f061346b..4b4ba99415 100644
--- a/tools/inspector_protocol/lib/Values_cpp.template
+++ b/tools/inspector_protocol/lib/Values_cpp.template
@@ -1,3 +1,5 @@
+// This file is generated by Values_cpp.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -58,8 +60,162 @@ void escapeStringForJSONInternal(const Char* str, unsigned len,
     }
 }
 
+// When parsing CBOR, we limit recursion depth for objects and arrays
+// to this constant.
+static constexpr int kStackLimitValues = 1000;
+
+// Below are three parsing routines for CBOR, which cover enough
+// to roundtrip JSON messages.
+std::unique_ptr<DictionaryValue> parseMap(int32_t stack_depth, CBORTokenizer* tokenizer);
+std::unique_ptr<ListValue> parseArray(int32_t stack_depth, CBORTokenizer* tokenizer);
+std::unique_ptr<Value> parseValue(int32_t stack_depth, CBORTokenizer* tokenizer);
+
+// |bytes| must start with the indefinite length array byte, so basically,
+// ParseArray may only be called after an indefinite length array has been
+// detected.
+std::unique_ptr<ListValue> parseArray(int32_t stack_depth, CBORTokenizer* tokenizer) {
+  DCHECK(tokenizer->TokenTag() == CBORTokenTag::ARRAY_START);
+  tokenizer->Next();
+  auto list = ListValue::create();
+  while (tokenizer->TokenTag() != CBORTokenTag::STOP) {
+    // Error::CBOR_UNEXPECTED_EOF_IN_ARRAY
+    if (tokenizer->TokenTag() == CBORTokenTag::DONE) return nullptr;
+    if (tokenizer->TokenTag() == CBORTokenTag::ERROR_VALUE) return nullptr;
+    // Parse value.
+    auto value = parseValue(stack_depth, tokenizer);
+    if (!value) return nullptr;
+    list->pushValue(std::move(value));
+  }
+  tokenizer->Next();
+  return list;
+}
+
+std::unique_ptr<Value> parseValue(
+    int32_t stack_depth, CBORTokenizer* tokenizer) {
+  // Error::CBOR_STACK_LIMIT_EXCEEDED
+  if (stack_depth > kStackLimitValues) return nullptr;
+  // Skip past the envelope to get to what's inside.
+  if (tokenizer->TokenTag() == CBORTokenTag::ENVELOPE)
+    tokenizer->EnterEnvelope();
+  switch (tokenizer->TokenTag()) {
+    case CBORTokenTag::ERROR_VALUE:
+      return nullptr;
+    case CBORTokenTag::DONE:
+      // Error::CBOR_UNEXPECTED_EOF_EXPECTED_VALUE
+      return nullptr;
+    case CBORTokenTag::TRUE_VALUE: {
+      std::unique_ptr<Value> value = FundamentalValue::create(true);
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::FALSE_VALUE: {
+      std::unique_ptr<Value> value = FundamentalValue::create(false);
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::NULL_VALUE: {
+      std::unique_ptr<Value> value = FundamentalValue::null();
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::INT32: {
+      std::unique_ptr<Value> value = FundamentalValue::create(tokenizer->GetInt32());
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::DOUBLE: {
+      std::unique_ptr<Value> value = FundamentalValue::create(tokenizer->GetDouble());
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::STRING8: {
+      span<uint8_t> str = tokenizer->GetString8();
+      std::unique_ptr<Value> value = StringValue::create(StringUtil::fromUTF8(str.data(), str.size()));
+      tokenizer->Next();
+      return value;
+    }
+    case CBORTokenTag::STRING16:
+      // NOT SUPPORTED YET.
+      return nullptr;
+    case CBORTokenTag::BINARY: {
+      span<uint8_t> payload = tokenizer->GetBinary();
+      tokenizer->Next();
+      return BinaryValue::create(Binary::fromSpan(payload.data(), payload.size()));
+    }
+    case CBORTokenTag::MAP_START:
+      return parseMap(stack_depth + 1, tokenizer);
+    case CBORTokenTag::ARRAY_START:
+      return parseArray(stack_depth + 1, tokenizer);
+    default:
+      // Error::CBOR_UNSUPPORTED_VALUE
+      return nullptr;
+  }
+}
+
+// |bytes| must start with the indefinite length array byte, so basically,
+// ParseArray may only be called after an indefinite length array has been
+// detected.
+std::unique_ptr<DictionaryValue> parseMap(
+    int32_t stack_depth, CBORTokenizer* tokenizer) {
+  auto dict = DictionaryValue::create();
+  tokenizer->Next();
+  while (tokenizer->TokenTag() != CBORTokenTag::STOP) {
+    if (tokenizer->TokenTag() == CBORTokenTag::DONE) {
+      // Error::CBOR_UNEXPECTED_EOF_IN_MAP
+      return nullptr;
+    }
+    if (tokenizer->TokenTag() == CBORTokenTag::ERROR_VALUE) return nullptr;
+    // Parse key.
+    String key;
+    if (tokenizer->TokenTag() == CBORTokenTag::STRING8) {
+      span<uint8_t> key_span = tokenizer->GetString8();
+      key = StringUtil::fromUTF8(key_span.data(), key_span.size());
+      tokenizer->Next();
+    } else if (tokenizer->TokenTag() == CBORTokenTag::STRING16) {
+      return nullptr;  // STRING16 not supported yet.
+    } else {
+      // Error::CBOR_INVALID_MAP_KEY
+      return nullptr;
+    }
+    // Parse value.
+    auto value = parseValue(stack_depth, tokenizer);
+    if (!value) return nullptr;
+    dict->setValue(key, std::move(value));
+  }
+  tokenizer->Next();
+  return dict;
+}
+
 } // anonymous namespace
 
+// static
+std::unique_ptr<Value> Value::parseBinary(const uint8_t* data, size_t size) {
+  span<uint8_t> bytes(data, size);
+
+  // Error::CBOR_NO_INPUT
+  if (bytes.empty()) return nullptr;
+
+  // Error::CBOR_INVALID_START_BYTE
+  // TODO(johannes): EncodeInitialByteForEnvelope() method.
+  if (bytes[0] != 0xd8) return nullptr;
+
+  CBORTokenizer tokenizer(bytes);
+  if (tokenizer.TokenTag() == CBORTokenTag::ERROR_VALUE) return nullptr;
+
+  // We checked for the envelope start byte above, so the tokenizer
+  // must agree here, since it's not an error.
+  DCHECK(tokenizer.TokenTag() == CBORTokenTag::ENVELOPE);
+  tokenizer.EnterEnvelope();
+  // Error::MAP_START_EXPECTED
+  if (tokenizer.TokenTag() != CBORTokenTag::MAP_START) return nullptr;
+  std::unique_ptr<Value> result = parseMap(/*stack_depth=*/1, &tokenizer);
+  if (!result) return nullptr;
+  if (tokenizer.TokenTag() == CBORTokenTag::DONE) return result;
+  if (tokenizer.TokenTag() == CBORTokenTag::ERROR_VALUE) return nullptr;
+  // Error::CBOR_TRAILING_JUNK
+  return nullptr;
+}
+
 bool Value::asBoolean(bool*) const
 {
     return false;
@@ -80,7 +236,7 @@ bool Value::asString(String*) const
     return false;
 }
 
-bool Value::asSerialized(String*) const
+bool Value::asBinary(Binary*) const
 {
     return false;
 }
@@ -91,12 +247,17 @@ void Value::writeJSON(StringBuilder* output) const
     StringUtil::builderAppend(*output, nullValueString, 4);
 }
 
+void Value::writeBinary(std::vector<uint8_t>* bytes) const {
+    DCHECK(m_type == TypeNull);
+    bytes->push_back(EncodeNull());
+}
+
 std::unique_ptr<Value> Value::clone() const
 {
     return Value::null();
 }
 
-String Value::serialize()
+String Value::toJSONString() const
 {
     StringBuilder result;
     StringUtil::builderReserve(result, 512);
@@ -104,6 +265,16 @@ String Value::serialize()
     return StringUtil::builderToString(result);
 }
 
+String Value::serializeToJSON() {
+    return toJSONString();
+}
+
+std::vector<uint8_t> Value::serializeToBinary() {
+    std::vector<uint8_t> bytes;
+    writeBinary(&bytes);
+    return bytes;
+}
+
 bool FundamentalValue::asBoolean(bool* output) const
 {
     if (type() != TypeBoolean)
@@ -152,6 +323,22 @@ void FundamentalValue::writeJSON(StringBuilder* output) const
     }
 }
 
+void FundamentalValue::writeBinary(std::vector<uint8_t>* bytes) const {
+    switch (type()) {
+    case TypeDouble:
+        EncodeDouble(m_doubleValue, bytes);
+        return;
+    case TypeInteger:
+        EncodeInt32(m_integerValue, bytes);
+        return;
+    case TypeBoolean:
+        bytes->push_back(m_boolValue ? EncodeTrue() : EncodeFalse());
+        return;
+    default:
+        DCHECK(false);
+    }
+}
+
 std::unique_ptr<Value> FundamentalValue::clone() const
 {
     switch (type()) {
@@ -176,26 +363,53 @@ void StringValue::writeJSON(StringBuilder* output) const
     StringUtil::builderAppendQuotedString(*output, m_stringValue);
 }
 
+void StringValue::writeBinary(std::vector<uint8_t>* bytes) const {
+    StringUTF8Adapter utf8(m_stringValue);
+    EncodeString8(span<uint8_t>(reinterpret_cast<const uint8_t*>(utf8.Data()),
+                  utf8.length()), bytes);
+}
+
 std::unique_ptr<Value> StringValue::clone() const
 {
     return StringValue::create(m_stringValue);
 }
 
-bool SerializedValue::asSerialized(String* output) const
+bool BinaryValue::asBinary(Binary* output) const
 {
-    *output = m_serializedValue;
+    *output = m_binaryValue;
     return true;
 }
 
+void BinaryValue::writeJSON(StringBuilder* output) const
+{
+    DCHECK(type() == TypeBinary);
+    StringUtil::builderAppendQuotedString(*output, m_binaryValue.toBase64());
+}
+
+void BinaryValue::writeBinary(std::vector<uint8_t>* bytes) const {
+    EncodeBinary(span<uint8_t>(m_binaryValue.data(), m_binaryValue.size()), bytes);
+}
+
+std::unique_ptr<Value> BinaryValue::clone() const
+{
+    return BinaryValue::create(m_binaryValue);
+}
+
 void SerializedValue::writeJSON(StringBuilder* output) const
 {
     DCHECK(type() == TypeSerialized);
-    StringUtil::builderAppend(*output, m_serializedValue);
+    StringUtil::builderAppend(*output, m_serializedJSON);
+}
+
+void SerializedValue::writeBinary(std::vector<uint8_t>* output) const
+{
+    DCHECK(type() == TypeSerialized);
+    output->insert(output->end(), m_serializedBinary.begin(), m_serializedBinary.end());
 }
 
 std::unique_ptr<Value> SerializedValue::clone() const
 {
-    return SerializedValue::create(m_serializedValue);
+    return std::unique_ptr<SerializedValue>(new SerializedValue(m_serializedJSON, m_serializedBinary));
 }
 
 DictionaryValue::~DictionaryValue()
@@ -335,6 +549,23 @@ void DictionaryValue::writeJSON(StringBuilder* output) const
     StringUtil::builderAppend(*output, '}');
 }
 
+void DictionaryValue::writeBinary(std::vector<uint8_t>* bytes) const {
+    EnvelopeEncoder encoder;
+    encoder.EncodeStart(bytes);
+    bytes->push_back(EncodeIndefiniteLengthMapStart());
+    for (size_t i = 0; i < m_order.size(); ++i) {
+        const String& key = m_order[i];
+        Dictionary::const_iterator value = m_data.find(key);
+        DCHECK(value != m_data.cend() && value->second);
+        StringUTF8Adapter utf8(key);
+        EncodeString8(span<uint8_t>(reinterpret_cast<const uint8_t*>(utf8.Data()),
+	                            utf8.length()), bytes);
+        value->second->writeBinary(bytes);
+    }
+    bytes->push_back(EncodeStop());
+    encoder.EncodeStop(bytes);
+}
+
 std::unique_ptr<Value> DictionaryValue::clone() const
 {
     std::unique_ptr<DictionaryValue> result = DictionaryValue::create();
@@ -369,6 +600,17 @@ void ListValue::writeJSON(StringBuilder* output) const
     StringUtil::builderAppend(*output, ']');
 }
 
+void ListValue::writeBinary(std::vector<uint8_t>* bytes) const {
+    EnvelopeEncoder encoder;
+    encoder.EncodeStart(bytes);
+    bytes->push_back(EncodeIndefiniteLengthArrayStart());
+    for (size_t i = 0; i < m_data.size(); ++i) {
+        m_data[i]->writeBinary(bytes);
+    }
+    bytes->push_back(EncodeStop());
+    encoder.EncodeStop(bytes);
+}
+
 std::unique_ptr<Value> ListValue::clone() const
 {
     std::unique_ptr<ListValue> result = ListValue::create();
diff --git a/tools/inspector_protocol/lib/Values_h.template b/tools/inspector_protocol/lib/Values_h.template
index 3638b34b4e..4a2e58f4cd 100644
--- a/tools/inspector_protocol/lib/Values_h.template
+++ b/tools/inspector_protocol/lib/Values_h.template
@@ -1,3 +1,5 @@
+// This file is generated by Values_h.template.
+
 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
@@ -6,7 +8,6 @@
 #define {{"_".join(config.protocol.namespace)}}_Values_h
 
 //#include "Allocator.h"
-//#include "Collections.h"
 //#include "Forward.h"
 
 {% for namespace in config.protocol.namespace %}
@@ -27,15 +28,19 @@ public:
         return std::unique_ptr<Value>(new Value());
     }
 
+    static std::unique_ptr<Value> parseBinary(const uint8_t* data, size_t size);
+
     enum ValueType {
         TypeNull = 0,
         TypeBoolean,
         TypeInteger,
         TypeDouble,
         TypeString,
+        TypeBinary,
         TypeObject,
         TypeArray,
-        TypeSerialized
+        TypeSerialized,
+        TypeImported
     };
 
     ValueType type() const { return m_type; }
@@ -46,11 +51,14 @@ public:
     virtual bool asDouble(double* output) const;
     virtual bool asInteger(int* output) const;
     virtual bool asString(String* output) const;
-    virtual bool asSerialized(String* output) const;
+    virtual bool asBinary(Binary* output) const;
 
     virtual void writeJSON(StringBuilder* output) const;
+    virtual void writeBinary(std::vector<uint8_t>* bytes) const;
     virtual std::unique_ptr<Value> clone() const;
-    String serialize() override;
+    String toJSONString() const;
+    String serializeToJSON() override;
+    std::vector<uint8_t> serializeToBinary() override;
 
 protected:
     Value() : m_type(TypeNull) { }
@@ -84,6 +92,7 @@ public:
     bool asDouble(double* output) const override;
     bool asInteger(int* output) const override;
     void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
     std::unique_ptr<Value> clone() const override;
 
 private:
@@ -112,6 +121,7 @@ public:
 
     bool asString(String* output) const override;
     void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
     std::unique_ptr<Value> clone() const override;
 
 private:
@@ -121,21 +131,47 @@ private:
     String m_stringValue;
 };
 
+class {{config.lib.export_macro}} BinaryValue : public Value {
+public:
+    static std::unique_ptr<BinaryValue> create(const Binary& value)
+    {
+        return std::unique_ptr<BinaryValue>(new BinaryValue(value));
+    }
+
+    bool asBinary(Binary* output) const override;
+    void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
+    std::unique_ptr<Value> clone() const override;
+
+private:
+    explicit BinaryValue(const Binary& value) : Value(TypeBinary), m_binaryValue(value) { }
+
+    Binary m_binaryValue;
+};
+
 class {{config.lib.export_macro}} SerializedValue : public Value {
 public:
-    static std::unique_ptr<SerializedValue> create(const String& value)
+    static std::unique_ptr<SerializedValue> fromJSON(const String& value)
     {
         return std::unique_ptr<SerializedValue>(new SerializedValue(value));
     }
 
-    bool asSerialized(String* output) const override;
+    static std::unique_ptr<SerializedValue> fromBinary(std::vector<uint8_t> value)
+    {
+        return std::unique_ptr<SerializedValue>(new SerializedValue(std::move(value)));
+    }
+
     void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
     std::unique_ptr<Value> clone() const override;
 
 private:
-    explicit SerializedValue(const String& value) : Value(TypeSerialized), m_serializedValue(value) { }
-
-    String m_serializedValue;
+    explicit SerializedValue(const String& json) : Value(TypeSerialized), m_serializedJSON(json) { }
+    explicit SerializedValue(std::vector<uint8_t> binary) : Value(TypeSerialized), m_serializedBinary(std::move(binary)) { }
+    SerializedValue(const String& json, const std::vector<uint8_t>& binary)
+        : Value(TypeSerialized), m_serializedJSON(json), m_serializedBinary(binary) { }
+    String m_serializedJSON;
+    std::vector<uint8_t> m_serializedBinary;
 };
 
 class {{config.lib.export_macro}} DictionaryValue : public Value {
@@ -159,6 +195,7 @@ public:
     }
 
     void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
     std::unique_ptr<Value> clone() const override;
 
     size_t size() const { return m_data.size(); }
@@ -200,7 +237,7 @@ private:
             m_order.push_back(key);
     }
 
-    using Dictionary = protocol::HashMap<String, std::unique_ptr<Value>>;
+    using Dictionary = std::unordered_map<String, std::unique_ptr<Value>>;
     Dictionary m_data;
     std::vector<String> m_order;
 };
@@ -227,6 +264,7 @@ public:
     ~ListValue() override;
 
     void writeJSON(StringBuilder* output) const override;
+    void writeBinary(std::vector<uint8_t>* bytes) const override;
     std::unique_ptr<Value> clone() const override;
 
     void pushValue(std::unique_ptr<Value>);
diff --git a/tools/inspector_protocol/lib/base_string_adapter_cc.template b/tools/inspector_protocol/lib/base_string_adapter_cc.template
new file mode 100644
index 0000000000..ed3316446f
--- /dev/null
+++ b/tools/inspector_protocol/lib/base_string_adapter_cc.template
@@ -0,0 +1,304 @@
+// This file is generated by DispatcherBase_cpp.template.
+
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include {{format_include(config.protocol.package, "base_string_adapter")}}
+#include {{format_include(config.protocol.package, "Protocol")}}
+
+#include <utility>
+#include "base/base64.h"
+#include "base/json/json_reader.h"
+#include "base/memory/ptr_util.h"
+#include "base/strings/string16.h"
+#include "base/strings/stringprintf.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/values.h"
+
+{% for namespace in config.protocol.namespace %}
+namespace {{namespace}} {
+{% endfor %}
+
+std::unique_ptr<protocol::Value> toProtocolValue(
+    const base::Value* value, int depth) {
+  if (!value || !depth)
+    return nullptr;
+  if (value->is_none())
+    return protocol::Value::null();
+  if (value->is_bool()) {
+    bool inner;
+    value->GetAsBoolean(&inner);
+    return protocol::FundamentalValue::create(inner);
+  }
+  if (value->is_int()) {
+    int inner;
+    value->GetAsInteger(&inner);
+    return protocol::FundamentalValue::create(inner);
+  }
+  if (value->is_double()) {
+    double inner;
+    value->GetAsDouble(&inner);
+    return protocol::FundamentalValue::create(inner);
+  }
+  if (value->is_string()) {
+    std::string inner;
+    value->GetAsString(&inner);
+    return protocol::StringValue::create(inner);
+  }
+  if (value->is_list()) {
+    const base::ListValue* list = nullptr;
+    value->GetAsList(&list);
+    std::unique_ptr<protocol::ListValue> result = protocol::ListValue::create();
+    for (size_t i = 0; i < list->GetSize(); i++) {
+      const base::Value* item = nullptr;
+      list->Get(i, &item);
+      std::unique_ptr<protocol::Value> converted =
+          toProtocolValue(item, depth - 1);
+      if (converted)
+        result->pushValue(std::move(converted));
+    }
+    return std::move(result);
+  }
+  if (value->is_dict()) {
+    const base::DictionaryValue* dictionary = nullptr;
+    value->GetAsDictionary(&dictionary);
+    std::unique_ptr<protocol::DictionaryValue> result =
+        protocol::DictionaryValue::create();
+    for (base::DictionaryValue::Iterator it(*dictionary);
+        !it.IsAtEnd(); it.Advance()) {
+      std::unique_ptr<protocol::Value> converted =
+          toProtocolValue(&it.value(), depth - 1);
+      if (converted)
+        result->setValue(it.key(), std::move(converted));
+    }
+    return std::move(result);
+  }
+  return nullptr;
+}
+
+std::unique_ptr<base::Value> toBaseValue(Value* value, int depth) {
+  if (!value || !depth)
+    return nullptr;
+  if (value->type() == Value::TypeNull)
+    return std::make_unique<base::Value>();
+  if (value->type() == Value::TypeBoolean) {
+    bool inner;
+    value->asBoolean(&inner);
+    return base::WrapUnique(new base::Value(inner));
+  }
+  if (value->type() == Value::TypeInteger) {
+    int inner;
+    value->asInteger(&inner);
+    return base::WrapUnique(new base::Value(inner));
+  }
+  if (value->type() == Value::TypeDouble) {
+    double inner;
+    value->asDouble(&inner);
+    return base::WrapUnique(new base::Value(inner));
+  }
+  if (value->type() == Value::TypeString) {
+    std::string inner;
+    value->asString(&inner);
+    return base::WrapUnique(new base::Value(inner));
+  }
+  if (value->type() == Value::TypeArray) {
+    ListValue* list = ListValue::cast(value);
+    std::unique_ptr<base::ListValue> result(new base::ListValue());
+    for (size_t i = 0; i < list->size(); i++) {
+      std::unique_ptr<base::Value> converted =
+          toBaseValue(list->at(i), depth - 1);
+      if (converted)
+        result->Append(std::move(converted));
+    }
+    return std::move(result);
+  }
+  if (value->type() == Value::TypeObject) {
+    DictionaryValue* dict = DictionaryValue::cast(value);
+    std::unique_ptr<base::DictionaryValue> result(new base::DictionaryValue());
+    for (size_t i = 0; i < dict->size(); i++) {
+      DictionaryValue::Entry entry = dict->at(i);
+      std::unique_ptr<base::Value> converted =
+          toBaseValue(entry.second, depth - 1);
+      if (converted)
+        result->SetWithoutPathExpansion(entry.first, std::move(converted));
+    }
+    return std::move(result);
+  }
+  return nullptr;
+}
+
+// static
+std::unique_ptr<Value> StringUtil::parseMessage(
+    const std::string& message, bool binary) {
+  if (binary) {
+    return Value::parseBinary(
+        reinterpret_cast<const uint8_t*>(message.data()),
+        message.length());
+  }
+  std::unique_ptr<base::Value> value = base::JSONReader::Read(message);
+  return toProtocolValue(value.get(), 1000);
+}
+
+// static
+ProtocolMessage StringUtil::jsonToMessage(String message) {
+  return message;
+}
+
+// static
+ProtocolMessage StringUtil::binaryToMessage(std::vector<uint8_t> message) {
+  // TODO(pfeldman): figure out what to do with this copy.
+  return std::string(reinterpret_cast<const char*>(message.data()), message.size());
+}
+
+StringBuilder::StringBuilder() {}
+
+StringBuilder::~StringBuilder() {}
+
+void StringBuilder::append(const std::string& s) {
+  string_ += s;
+}
+
+void StringBuilder::append(char c) {
+  string_ += c;
+}
+
+void StringBuilder::append(const char* characters, size_t length) {
+  string_.append(characters, length);
+}
+
+// static
+void StringUtil::builderAppendQuotedString(StringBuilder& builder,
+                                           const String& str) {
+  builder.append('"');
+  base::string16 str16 = base::UTF8ToUTF16(str);
+  escapeWideStringForJSON(reinterpret_cast<const uint16_t*>(&str16[0]),
+                          str16.length(), &builder);
+  builder.append('"');
+}
+
+std::string StringBuilder::toString() {
+  return string_;
+}
+
+void StringBuilder::reserveCapacity(size_t capacity) {
+  string_.reserve(capacity);
+}
+
+Binary::Binary() : bytes_(new base::RefCountedBytes) {}
+Binary::Binary(const Binary& binary) : bytes_(binary.bytes_) {}
+Binary::Binary(scoped_refptr<base::RefCountedMemory> bytes) : bytes_(bytes) {}
+Binary::~Binary() {}
+
+String Binary::toBase64() const {
+  std::string encoded;
+  base::Base64Encode(
+      base::StringPiece(reinterpret_cast<const char*>(bytes_->front()),
+                        bytes_->size()),
+      &encoded);
+  return encoded;
+}
+
+// static
+Binary Binary::fromBase64(const String& base64, bool* success) {
+  std::string decoded;
+  *success = base::Base64Decode(base::StringPiece(base64), &decoded);
+  if (*success) {
+    return Binary::fromString(std::move(decoded));
+  }
+  return Binary();
+}
+
+// static
+Binary Binary::fromRefCounted(scoped_refptr<base::RefCountedMemory> memory) {
+  return Binary(memory);
+}
+
+// static
+Binary Binary::fromVector(std::vector<uint8_t> data) {
+  return Binary(base::RefCountedBytes::TakeVector(&data));
+}
+
+// static
+Binary Binary::fromString(std::string data) {
+  return Binary(base::RefCountedString::TakeString(&data));
+}
+
+// static
+Binary Binary::fromSpan(const uint8_t* data, size_t size) {
+  return Binary(scoped_refptr<base::RefCountedBytes>(
+      new base::RefCountedBytes(data, size)));
+}
+
+namespace {
+int32_t ReadEnvelopeSize(const uint8_t* in) {
+  return (in[0] << 24) + (in[1] << 16) + (in[2] << 8) + in[3];
+}
+
+void WriteEnvelopeSize(uint32_t value, uint8_t* out) {
+  *(out++) = (value >> 24) & 0xFF;
+  *(out++) = (value >> 16) & 0xFF;
+  *(out++) = (value >> 8) & 0xFF;
+  *(out++) = (value) & 0xFF;
+}
+
+}
+
+bool AppendStringValueToMapBinary(base::StringPiece in,
+    base::StringPiece key, base::StringPiece value, std::string* out) {
+  if (in.size() < 1 + 1 + 4 + 1 + 1)
+    return false;
+  const uint8_t* envelope = reinterpret_cast<const uint8_t*>(in.data());
+  if (cbor::kInitialByteForEnvelope != envelope[0])
+    return false;
+  if (cbor::kInitialByteFor32BitLengthByteString != envelope[1])
+    return false;
+  if (cbor::kInitialByteIndefiniteLengthMap != envelope[6])
+    return false;
+
+  uint32_t envelope_size = ReadEnvelopeSize(envelope + 2);
+  if (envelope_size + 2 + 4 != in.size())
+    return false;
+  if (cbor::kStopByte != static_cast<uint8_t>(*in.rbegin()))
+    return false;
+
+  std::vector<uint8_t> encoded_entry;
+  encoded_entry.reserve(1 + 4 + key.size() + 1 + 4 + value.size());
+  span<uint8_t> key_span(
+      reinterpret_cast<const uint8_t*>(key.data()), key.size());
+  EncodeString8(key_span, &encoded_entry);
+  span<uint8_t> value_span(
+      reinterpret_cast<const uint8_t*>(value.data()), value.size());
+  EncodeString8(value_span, &encoded_entry);
+
+  out->clear();
+  out->reserve(in.size() + encoded_entry.size());
+  out->append(in.begin(), in.end() - 1);
+  out->append(reinterpret_cast<const char*>(encoded_entry.data()),
+      encoded_entry.size());
+  out->append(1, static_cast<char>(cbor::kStopByte));
+  std::size_t new_size = envelope_size + out->size() - in.size();
+  if (new_size > static_cast<std::size_t>(
+      std::numeric_limits<uint32_t>::max())) {
+    return false;
+  }
+  WriteEnvelopeSize(new_size, reinterpret_cast<uint8_t*>(&*out->begin() + 2));
+  return true;
+}
+
+bool AppendStringValueToMapJSON(base::StringPiece in,
+    base::StringPiece key, base::StringPiece value, std::string* out) {
+  if (!in.length() || *in.rbegin() != '}')
+    return false;
+  std::string suffix =
+      base::StringPrintf(", \"%s\": \"%s\"}", key.begin(), value.begin());
+  out->clear();
+  out->reserve(in.length() + suffix.length() - 1);
+  out->append(in.data(), in.length() - 1);
+  out->append(suffix);
+  return true;
+}
+
+{% for namespace in config.protocol.namespace %}
+} // namespace {{namespace}}
+{% endfor %}
diff --git a/tools/inspector_protocol/lib/base_string_adapter_h.template b/tools/inspector_protocol/lib/base_string_adapter_h.template
new file mode 100644
index 0000000000..b0215e0745
--- /dev/null
+++ b/tools/inspector_protocol/lib/base_string_adapter_h.template
@@ -0,0 +1,150 @@
+// This file is generated by Parser_h.template.
+
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef {{"_".join(config.protocol.namespace)}}_BASE_STRING_ADAPTER_H
+#define {{"_".join(config.protocol.namespace)}}_BASE_STRING_ADAPTER_H
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/strings/string_number_conversions.h"
+{% if config.lib.export_header %}
+#include "{{config.lib.export_header}}"
+{% endif %}
+
+namespace base {
+class Value;
+}
+
+{% for namespace in config.protocol.namespace %}
+namespace {{namespace}} {
+{% endfor %}
+
+class Value;
+
+using String = std::string;
+using ProtocolMessage = std::string;
+
+class {{config.lib.export_macro}} StringUTF8Adapter {
+ public:
+  StringUTF8Adapter(const std::string& string) : string_(string) { }
+  const char* Data() const { return string_.data(); }
+  size_t length() const { return string_.length(); }
+
+ private:
+  const std::string& string_;
+};
+
+class {{config.lib.export_macro}} StringBuilder {
+ public:
+  StringBuilder();
+  ~StringBuilder();
+  void append(const String&);
+  void append(char);
+  void append(const char*, size_t);
+  String toString();
+  void reserveCapacity(size_t);
+
+ private:
+  std::string string_;
+};
+
+class {{config.lib.export_macro}} StringUtil {
+ public:
+  static String substring(const String& s, unsigned pos, unsigned len) {
+    return s.substr(pos, len);
+  }
+  static String fromInteger(int number) { return base::NumberToString(number); }
+  static String fromDouble(double number) {
+    String s = base::NumberToString(number);
+    if (!s.empty()) {  // .123 -> 0.123; -.123 -> -0.123 for valid JSON.
+      if (s[0] == '.')
+        s.insert(/*index=*/ 0, /*count=*/ 1, /*ch=*/ '0');
+      else if (s[0] == '-' && s.size() >= 2 && s[1] == '.')
+        s.insert(/*index=*/ 1, /*count=*/ 1, /*ch=*/ '0');
+    }
+    return s;
+  }
+  static double toDouble(const char* s, size_t len, bool* ok) {
+    double v = 0.0;
+    *ok = base::StringToDouble(std::string(s, len), &v);
+    return *ok ? v : 0.0;
+  }
+  static size_t find(const String& s, const char* needle) {
+    return s.find(needle);
+  }
+  static size_t find(const String& s, const String& needle) {
+    return s.find(needle);
+  }
+  static const size_t kNotFound = static_cast<size_t>(-1);
+  static void builderAppend(StringBuilder& builder, const String& s) {
+    builder.append(s);
+  }
+  static void builderAppend(StringBuilder& builder, char c) {
+    builder.append(c);
+  }
+  static void builderAppend(StringBuilder& builder, const char* s, size_t len) {
+    builder.append(s, len);
+  }
+  static void builderAppendQuotedString(StringBuilder& builder,
+                                        const String& str);
+  static void builderReserve(StringBuilder& builder, unsigned capacity) {
+    builder.reserveCapacity(capacity);
+  }
+  static String builderToString(StringBuilder& builder) {
+    return builder.toString();
+  }
+
+  static std::unique_ptr<Value> parseMessage(const std::string& message, bool binary);
+  static ProtocolMessage jsonToMessage(String message);
+  static ProtocolMessage binaryToMessage(std::vector<uint8_t> message);
+
+  static String fromUTF8(const uint8_t* data, size_t length) {
+    return std::string(reinterpret_cast<const char*>(data), length);
+  }
+};
+
+// A read-only sequence of uninterpreted bytes with reference-counted storage.
+class {{config.lib.export_macro}} Binary {
+ public:
+  Binary(const Binary&);
+  Binary();
+  ~Binary();
+
+  const uint8_t* data() const { return bytes_->front(); }
+  size_t size() const { return bytes_->size(); }
+  scoped_refptr<base::RefCountedMemory> bytes() const { return bytes_; }
+
+  String toBase64() const;
+
+  static Binary fromBase64(const String& base64, bool* success);
+  static Binary fromRefCounted(scoped_refptr<base::RefCountedMemory> memory);
+  static Binary fromVector(std::vector<uint8_t> data);
+  static Binary fromString(std::string data);
+  static Binary fromSpan(const uint8_t* data, size_t size);
+
+ private:
+  explicit Binary(scoped_refptr<base::RefCountedMemory> bytes);
+  scoped_refptr<base::RefCountedMemory> bytes_;
+};
+
+std::unique_ptr<Value> toProtocolValue(const base::Value* value, int depth);
+std::unique_ptr<base::Value> toBaseValue(Value* value, int depth);
+
+bool AppendStringValueToMapBinary(base::StringPiece in,
+    base::StringPiece key, base::StringPiece value, std::string* out);
+bool AppendStringValueToMapJSON(base::StringPiece in,
+    base::StringPiece key, base::StringPiece value, std::string* out);
+
+{% for namespace in config.protocol.namespace %}
+} // namespace {{namespace}}
+{% endfor %}
+
+#endif // !defined({{"_".join(config.protocol.namespace)}}_BASE_STRING_ADAPTER_H)
diff --git a/tools/inspector_protocol/ConvertProtocolToJSON.py b/tools/inspector_protocol/pdl.py
index 56fc09d78c..43111e944b 100644
--- a/tools/inspector_protocol/ConvertProtocolToJSON.py
+++ b/tools/inspector_protocol/pdl.py
@@ -1,28 +1,31 @@
-# Copyright 2017 The Chromium Authors. All rights reserved.
+# Copyright 2018 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+from __future__ import print_function
 import collections
 import json
 import os.path
 import re
 import sys
 
-file_name = None
 description = ''
 
-primitiveTypes = ['integer', 'number', 'boolean', 'string', 'object', 'any', 'array']
 
+primitiveTypes = ['integer', 'number', 'boolean', 'string', 'object', 'any', 'array', 'binary']
 
-def assignType(item, type, isArray=False):
-    if isArray:
+
+def assignType(item, type, is_array=False, map_binary_to_string=False):
+    if is_array:
         item['type'] = 'array'
         item['items'] = collections.OrderedDict()
-        assignType(item['items'], type)
+        assignType(item['items'], type, False, map_binary_to_string)
         return
 
     if type == 'enum':
         type = 'string'
+    if map_binary_to_string and type == 'binary':
+        type = 'string'
     if type in primitiveTypes:
         item['type'] = type
     else:
@@ -43,7 +46,7 @@ def createItem(d, experimental, deprecated, name=None):
     return result
 
 
-def parse(data):
+def parse(data, file_name, map_binary_to_string=False):
     protocol = collections.OrderedDict()
     protocol['version'] = collections.OrderedDict()
     protocol['domains'] = []
@@ -89,7 +92,7 @@ def parse(data):
             if 'types' not in domain:
                 domain['types'] = []
             item = createItem({'id': match.group(3)}, match.group(1), match.group(2))
-            assignType(item, match.group(5), match.group(4))
+            assignType(item, match.group(5), match.group(4), map_binary_to_string)
             domain['types'].append(item)
             continue
 
@@ -116,7 +119,7 @@ def parse(data):
             param = createItem({}, match.group(1), match.group(2), match.group(6))
             if match.group(3):
                 param['optional'] = True
-            assignType(param, match.group(5), match.group(4))
+            assignType(param, match.group(5), match.group(4), map_binary_to_string)
             if match.group(5) == 'enum':
                 enumliterals = param['enum'] = []
             subitems.append(param)
@@ -157,27 +160,12 @@ def parse(data):
             enumliterals.append(trimLine)
             continue
 
-        print 'Error in %s:%s, illegal token: \t%s' % (file_name, i, line)
+        print('Error in %s:%s, illegal token: \t%s' % (file_name, i, line))
         sys.exit(1)
     return protocol
 
-def main(argv):
-    if len(argv) < 2:
-        sys.stderr.write("Usage: %s <protocol.pdl> <protocol.json>\n" % sys.argv[0])
-        return 1
-    global file_name
-    file_name = os.path.normpath(argv[0])
-    input_file = open(file_name, "r")
-    pdl_string = input_file.read()
-    protocol = parse(pdl_string)
-    output_file = open(argv[0].replace('.pdl', '.json'), 'wb')
-    json.dump(protocol, output_file, indent=4, separators=(',', ': '))
-    output_file.close()
-
-    output_file = open(os.path.normpath(argv[1]), 'wb')
-    json.dump(protocol, output_file, indent=4, separators=(',', ': '))
-    output_file.close()
-
-
-if __name__ == '__main__':
-    sys.exit(main(sys.argv[1:]))
+
+def loads(data, file_name, map_binary_to_string=False):
+    if file_name.endswith(".pdl"):
+        return parse(data, file_name, map_binary_to_string)
+    return json.loads(data)
diff --git a/tools/inspector_protocol/templates/Exported_h.template b/tools/inspector_protocol/templates/Exported_h.template
index 3d36ecffae..765f6c2135 100644
--- a/tools/inspector_protocol/templates/Exported_h.template
+++ b/tools/inspector_protocol/templates/Exported_h.template
@@ -1,4 +1,4 @@
-// This file is generated
+// This file is generated by Exported_h.template.
 
 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
@@ -15,6 +15,17 @@
 {% for namespace in config.protocol.namespace %}
 namespace {{namespace}} {
 {% endfor %}
+
+#ifndef {{"_".join(config.protocol.namespace)}}_exported_api_h
+#define {{"_".join(config.protocol.namespace)}}_exported_api_h
+class {{config.exported.export_macro}} Exported {
+public:
+    virtual {{config.exported.string_out}} toJSONString() const = 0;
+    virtual void writeBinary(std::vector<uint8_t>* out) const = 0;
+    virtual ~Exported() { }
+};
+#endif // !defined({{"_".join(config.protocol.namespace)}}_exported_api_h)
+
 namespace {{domain.domain}} {
 namespace API {
 
@@ -48,11 +59,10 @@ namespace {{param.name | to_title_case}}Enum {
   {% for type in domain.types %}
     {% if not (type.type == "object") or not ("properties" in type) or not protocol.is_exported(domain.domain, type.id) %}{% continue %}{% endif %}
 
-class {{config.exported.export_macro}} {{type.id}} {
+class {{config.exported.export_macro}} {{type.id}} : public Exported {
 public:
-    virtual {{config.exported.string_out}} toJSONString() const = 0;
-    virtual ~{{type.id}}() { }
     static std::unique_ptr<protocol::{{domain.domain}}::API::{{type.id}}> fromJSONString(const {{config.exported.string_in}}& json);
+    static std::unique_ptr<protocol::{{domain.domain}}::API::{{type.id}}> fromBinary(const uint8_t* data, size_t length);
 };
   {% endfor %}
 
diff --git a/tools/inspector_protocol/templates/Imported_h.template b/tools/inspector_protocol/templates/Imported_h.template
index 4c9d24bd5f..f2e576a9c4 100644
--- a/tools/inspector_protocol/templates/Imported_h.template
+++ b/tools/inspector_protocol/templates/Imported_h.template
@@ -1,4 +1,4 @@
-// This file is generated
+// This file is generated by Imported_h.template.
 
 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
@@ -17,6 +17,37 @@
 {% for namespace in config.protocol.namespace %}
 namespace {{namespace}} {
 {% endfor %}
+
+using Exported = {{"::".join(config.imported.namespace)}}::Exported;
+
+#ifndef {{"_".join(config.protocol.namespace)}}_imported_imported_h
+#define {{"_".join(config.protocol.namespace)}}_imported_imported_h
+
+class {{config.lib.export_macro}} ImportedValue : public Value {
+public:
+    static std::unique_ptr<ImportedValue> fromExported(const Exported* value) {
+        return std::unique_ptr<ImportedValue>(new ImportedValue(value));
+    }
+
+    void writeJSON(StringBuilder* output) const override {
+        auto json = m_exported->toJSONString();
+        String local_json = ({{config.imported.from_imported_string % "std::move(json)"}});
+        StringUtil::builderAppend(*output, local_json);
+    }
+    void writeBinary(std::vector<uint8_t>* output) const override {
+        m_exported->writeBinary(output);
+    }
+    std::unique_ptr<Value> clone() const override {
+        return std::unique_ptr<Value>(new ImportedValue(m_exported));
+    }
+
+private:
+    explicit ImportedValue(const Exported* exported) : Value(TypeImported), m_exported(exported) { }
+    const Exported* m_exported;
+};
+
+#endif // !defined({{"_".join(config.protocol.namespace)}}_imported_imported_h)
+
   {% for type in domain.types %}
     {% if not (type.type == "object") or not ("properties" in type) or not protocol.is_imported(domain.domain, type.id) %}{% continue %}{% endif %}
 
@@ -28,17 +59,18 @@ struct ValueConversions<{{"::".join(config.imported.namespace)}}::{{domain.domai
             errors->addError("value expected");
             return nullptr;
         }
-        String json = value->serialize();
-        auto result = {{"::".join(config.imported.namespace)}}::{{domain.domain}}::API::{{type.id}}::fromJSONString({{config.imported.to_imported_string % "json"}});
+
+        std::vector<uint8_t> binary;
+        value->writeBinary(&binary);
+        auto result = {{"::".join(config.imported.namespace)}}::{{domain.domain}}::API::{{type.id}}::fromBinary(binary.data(), binary.size());
         if (!result)
             errors->addError("cannot parse");
         return result;
     }
 
-    static std::unique_ptr<protocol::Value> toValue(const {{"::".join(config.imported.namespace)}}::{{domain.domain}}::API::{{type.id}}* value)
+    static std::unique_ptr<protocol::Value> toValue(const {{"::".join(config.imported.namespace)}}::{{domain.domain}}::API::{{type.id}}* exported)
     {
-        auto json = value->toJSONString();
-        return SerializedValue::create({{config.imported.from_imported_string % "std::move(json)"}});
+        return ImportedValue::fromExported(exported);
     }
 
     static std::unique_ptr<protocol::Value> toValue(const std::unique_ptr<{{"::".join(config.imported.namespace)}}::{{domain.domain}}::API::{{type.id}}>& value)
@@ -46,6 +78,7 @@ struct ValueConversions<{{"::".join(config.imported.namespace)}}::{{domain.domai
         return toValue(value.get());
     }
 };
+
   {% endfor %}
 
 {% for namespace in config.protocol.namespace %}
diff --git a/tools/inspector_protocol/templates/TypeBuilder_cpp.template b/tools/inspector_protocol/templates/TypeBuilder_cpp.template
index 026c1cdb8d..4ef60a6ea2 100644
--- a/tools/inspector_protocol/templates/TypeBuilder_cpp.template
+++ b/tools/inspector_protocol/templates/TypeBuilder_cpp.template
@@ -1,10 +1,10 @@
-// This file is generated
+// This file is generated by TypeBuilder_cpp.template.
 
 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include {{format_include(config.protocol.package, domain.domain)}}
+#include {{format_domain_include(config.protocol.package, domain.domain)}}
 
 #include {{format_include(config.protocol.package, "Protocol")}}
 
@@ -24,7 +24,7 @@ const char Metainfo::version[] = "{{domain.version}}";
 
 namespace {{type.id}}Enum {
       {% for literal in type.enum %}
-const char* {{ literal | dash_to_camelcase}} = "{{literal}}";
+const char {{ literal | dash_to_camelcase}}[] = "{{literal}}";
       {% endfor %}
 } // namespace {{type.id}}Enum
       {% if protocol.is_exported(domain.domain, type.id) %}
@@ -101,10 +101,15 @@ std::unique_ptr<{{type.id}}> {{type.id}}::clone() const
 
 {{config.exported.string_out}} {{type.id}}::toJSONString() const
 {
-    String json = toValue()->serialize();
+    String json = toValue()->serializeToJSON();
     return {{config.exported.to_string_out % "json"}};
 }
 
+void {{type.id}}::writeBinary(std::vector<uint8_t>* out) const
+{
+    toValue()->writeBinary(out);
+}
+
 // static
 std::unique_ptr<API::{{type.id}}> API::{{type.id}}::fromJSONString(const {{config.exported.string_in}}& json)
 {
@@ -114,6 +119,17 @@ std::unique_ptr<API::{{type.id}}> API::{{type.id}}::fromJSONString(const {{confi
         return nullptr;
     return protocol::{{domain.domain}}::{{type.id}}::fromValue(value.get(), &errors);
 }
+
+// static
+std::unique_ptr<API::{{type.id}}> API::{{type.id}}::fromBinary(const uint8_t* data, size_t length)
+{
+    ErrorSupport errors;
+    std::unique_ptr<Value> value = Value::parseBinary(data, length);
+    if (!value)
+        return nullptr;
+    return protocol::{{domain.domain}}::{{type.id}}::fromValue(value.get(), &errors);
+}
+
     {% endif %}
   {% endfor %}
 
@@ -187,19 +203,23 @@ void Frontend::flush()
     m_frontendChannel->flushProtocolNotifications();
 }
 
-void Frontend::sendRawNotification(const String& notification)
+void Frontend::sendRawNotification(String notification)
+{
+    m_frontendChannel->sendProtocolNotification(InternalRawNotification::fromJSON(std::move(notification)));
+}
+
+void Frontend::sendRawNotification(std::vector<uint8_t> notification)
 {
-    m_frontendChannel->sendProtocolNotification(InternalRawNotification::create(notification));
+    m_frontendChannel->sendProtocolNotification(InternalRawNotification::fromBinary(std::move(notification)));
 }
 
 // --------------------- Dispatcher.
 
 class DispatcherImpl : public protocol::DispatcherBase {
 public:
-    DispatcherImpl(FrontendChannel* frontendChannel, Backend* backend, bool fallThroughForNotFound)
+    DispatcherImpl(FrontendChannel* frontendChannel, Backend* backend)
         : DispatcherBase(frontendChannel)
-        , m_backend(backend)
-        , m_fallThroughForNotFound(fallThroughForNotFound) {
+        , m_backend(backend) {
   {% for command in domain.commands %}
     {% if "redirect" in command %}
       m_redirects["{{domain.domain}}.{{command.name}}"] = "{{command.redirect}}.{{command.name}}";
@@ -210,37 +230,35 @@ public:
   {% endfor %}
     }
     ~DispatcherImpl() override { }
-    DispatchResponse::Status dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject) override;
-    HashMap<String, String>& redirects() { return m_redirects; }
+    bool canDispatch(const String& method) override;
+    void dispatch(int callId, const String& method, const ProtocolMessage& message, std::unique_ptr<protocol::DictionaryValue> messageObject) override;
+    std::unordered_map<String, String>& redirects() { return m_redirects; }
 
 protected:
-    using CallHandler = DispatchResponse::Status (DispatcherImpl::*)(int callId, std::unique_ptr<DictionaryValue> messageObject, ErrorSupport* errors);
-    using DispatchMap = protocol::HashMap<String, CallHandler>;
+    using CallHandler = void (DispatcherImpl::*)(int callId, const String& method, const ProtocolMessage& message, std::unique_ptr<DictionaryValue> messageObject, ErrorSupport* errors);
+    using DispatchMap = std::unordered_map<String, CallHandler>;
     DispatchMap m_dispatchMap;
-    HashMap<String, String> m_redirects;
+    std::unordered_map<String, String> m_redirects;
 
   {% for command in domain.commands %}
     {% if "redirect" in command %}{% continue %}{% endif %}
     {% if not protocol.generate_command(domain.domain, command.name) %}{% continue %}{% endif %}
-    DispatchResponse::Status {{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport*);
+    void {{command.name}}(int callId, const String& method, const ProtocolMessage& message, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport*);
   {% endfor %}
 
     Backend* m_backend;
-    bool m_fallThroughForNotFound;
 };
 
-DispatchResponse::Status DispatcherImpl::dispatch(int callId, const String& method, std::unique_ptr<protocol::DictionaryValue> messageObject)
-{
-    protocol::HashMap<String, CallHandler>::iterator it = m_dispatchMap.find(method);
-    if (it == m_dispatchMap.end()) {
-        if (m_fallThroughForNotFound)
-            return DispatchResponse::kFallThrough;
-        reportProtocolError(callId, DispatchResponse::kMethodNotFound, "'" + method + "' wasn't found", nullptr);
-        return DispatchResponse::kError;
-    }
+bool DispatcherImpl::canDispatch(const String& method) {
+    return m_dispatchMap.find(method) != m_dispatchMap.end();
+}
 
+void DispatcherImpl::dispatch(int callId, const String& method, const ProtocolMessage& message, std::unique_ptr<protocol::DictionaryValue> messageObject)
+{
+    std::unordered_map<String, CallHandler>::iterator it = m_dispatchMap.find(method);
+    DCHECK(it != m_dispatchMap.end());
     protocol::ErrorSupport errors;
-    return (this->*(it->second))(callId, std::move(messageObject), &errors);
+    (this->*(it->second))(callId, method, message, std::move(messageObject), &errors);
 }
 
   {% for command in domain.commands %}
@@ -251,8 +269,8 @@ DispatchResponse::Status DispatcherImpl::dispatch(int callId, const String& meth
 
 class {{command_name_title}}CallbackImpl : public Backend::{{command_name_title}}Callback, public DispatcherBase::Callback {
 public:
-    {{command_name_title}}CallbackImpl(std::unique_ptr<DispatcherBase::WeakPtr> backendImpl, int callId, int callbackId)
-        : DispatcherBase::Callback(std::move(backendImpl), callId, callbackId) { }
+    {{command_name_title}}CallbackImpl(std::unique_ptr<DispatcherBase::WeakPtr> backendImpl, int callId, const String& method, const ProtocolMessage& message)
+        : DispatcherBase::Callback(std::move(backendImpl), callId, method, message) { }
 
     void sendSuccess(
       {%- for parameter in command.returns -%}
@@ -289,7 +307,7 @@ public:
 };
     {% endif %}
 
-DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport* errors)
+void DispatcherImpl::{{command.name}}(int callId, const String& method, const ProtocolMessage& message, std::unique_ptr<DictionaryValue> requestMessageObject, ErrorSupport* errors)
 {
     {% if "parameters" in command %}
     // Prepare input parameters.
@@ -312,7 +330,7 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
     errors->pop();
     if (errors->hasErrors()) {
         reportProtocolError(callId, DispatchResponse::kInvalidParams, kInvalidParamsString, errors);
-        return DispatchResponse::kError;
+        return;
     }
     {% endif %}
     {% if "returns" in command and not protocol.is_async_command(domain.domain, command.name) %}
@@ -343,8 +361,10 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
           &out_{{parameter.name}}
         {%- endfor %}
       {% endif %});
-    if (response.status() == DispatchResponse::kFallThrough)
-        return response.status();
+    if (response.status() == DispatchResponse::kFallThrough) {
+        channel()->fallThrough(callId, method, message);
+        return;
+    }
       {% if "returns" in command %}
     std::unique_ptr<protocol::DictionaryValue> result = DictionaryValue::create();
     if (response.status() == DispatchResponse::kSuccess) {
@@ -363,10 +383,10 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
     if (weak->get())
         weak->get()->sendResponse(callId, response);
       {% endif %}
-    return response.status();
+    return;
     {% else %}
     std::unique_ptr<DispatcherBase::WeakPtr> weak = weakPtr();
-    std::unique_ptr<{{command_name_title}}CallbackImpl> callback(new {{command.name | to_title_case}}CallbackImpl(weakPtr(), callId, nextCallbackId()));
+    std::unique_ptr<{{command_name_title}}CallbackImpl> callback(new {{command.name | to_title_case}}CallbackImpl(weakPtr(), callId, method, message));
     m_backend->{{command.name | to_method_case}}(
       {%- for property in command.parameters -%}
         {%- if not loop.first -%}, {% endif -%}
@@ -378,7 +398,7 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
       {%- endfor -%}
         {%- if command.parameters -%}, {% endif -%}
         std::move(callback));
-    return (weak->get() && weak->get()->lastCallbackFallThrough()) ? DispatchResponse::kFallThrough : DispatchResponse::kAsync;
+    return;
     {% endif %}
 }
   {% endfor %}
@@ -386,7 +406,7 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
 // static
 void Dispatcher::wire(UberDispatcher* uber, Backend* backend)
 {
-    std::unique_ptr<DispatcherImpl> dispatcher(new DispatcherImpl(uber->channel(), backend, uber->fallThroughForNotFound()));
+    std::unique_ptr<DispatcherImpl> dispatcher(new DispatcherImpl(uber->channel(), backend));
     uber->setupRedirects(dispatcher->redirects());
     uber->registerBackend("{{domain.domain}}", std::move(dispatcher));
 }
diff --git a/tools/inspector_protocol/templates/TypeBuilder_h.template b/tools/inspector_protocol/templates/TypeBuilder_h.template
index 744d496026..c670d65c46 100644
--- a/tools/inspector_protocol/templates/TypeBuilder_h.template
+++ b/tools/inspector_protocol/templates/TypeBuilder_h.template
@@ -1,4 +1,4 @@
-// This file is generated
+// This file is generated by TypeBuilder_h.template.
 
 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
@@ -15,7 +15,7 @@
 // and include Domain::API version from there.
 {% for name in domain.dependencies %}
   {% if protocol.is_imported_dependency(name) %}
-#include {{format_include(config.protocol.package, name)}}
+#include {{format_domain_include(config.protocol.package, name)}}
   {% endif %}
 {% endfor %}
 {% if protocol.is_exported_domain(domain.domain) %}
@@ -46,7 +46,7 @@ using {{type.id}} = {{protocol.resolve_type(type).type}};
 
 namespace {{type.id}}Enum {
       {% for literal in type.enum %}
-{{config.protocol.export_macro}} extern const char* {{ literal | dash_to_camelcase}};
+{{config.protocol.export_macro}} extern const char {{ literal | dash_to_camelcase}}[];
       {% endfor %}
 } // namespace {{type.id}}Enum
     {% endif %}
@@ -100,10 +100,13 @@ public:
     {% endfor %}
 
     std::unique_ptr<protocol::DictionaryValue> toValue() const;
-    String serialize() override { return toValue()->serialize(); }
+    String serializeToJSON() override { return toValue()->serializeToJSON(); }
+    std::vector<uint8_t> serializeToBinary() override { return toValue()->serializeToBinary(); }
+    String toJSON() const { return toValue()->toJSONString(); }
     std::unique_ptr<{{type.id}}> clone() const;
     {% if protocol.is_exported(domain.domain, type.id) %}
     {{config.exported.string_out}} toJSONString() const override;
+    void writeBinary(std::vector<uint8_t>* out) const override;
     {% endif %}
 
     template<int STATE>
@@ -266,7 +269,8 @@ public:
   {% endfor %}
 
     void flush();
-    void sendRawNotification(const String&);
+    void sendRawNotification(String);
+    void sendRawNotification(std::vector<uint8_t>);
 private:
     FrontendChannel* m_frontendChannel;
 };