src: Update trace event macros to V8 5.7 version

src/tracing/trace_event.h was updated by applying the following changes:

1) Include src/tracing/trace_event_common.h instead of the one from v8
base.

2) Replace all instances of base::Atomic with intptr_t (trace events can
only be generated from the main thread for now).

3) Replace instances of V8_INLINE with inline.

4) Eliminate uses of DCHECK.

5) Eliminate uses of V8_UNLIKELY, the branch predictor should be good
enough alone.

6) Change the namespace used by trace_event.h from v8::internal::tracing
to node::tracing.

7) Remove CallStatsScopedTracer class and related macros (they rely on
V8 implementation details).

8) Change ConvertableToTraceFormat to v8::ConvertableToTraceFormat.

9) Add function "static void SetCurrentPlatform(v8::Platform*
platform);" to the declaration of TraceEventHelper.

PR-URL: https://github.com/nodejs/node/pull/12127
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>

2 files changed, 1128 insertions, 1209 deletions

diff --git a/src/tracing/trace_event.h b/src/tracing/trace_event.h
index a035fd5150..4e2b6f4e88 100644
--- a/src/tracing/trace_event.h
+++ b/src/tracing/trace_event.h
@@ -8,1129 +8,12 @@
 #include <stddef.h>
 
 #include "v8-platform.h"
+#include "trace_event_common.h"
 
 // This header file defines implementation details of how the trace macros in
 // trace_event_common.h collect and store trace events. Anything not
 // implementation-specific should go in trace_macros_common.h instead of here.
 
-// From v8/base/trace_event/common/trace_event_common.h
-
-// This header file defines the set of trace_event macros without specifying
-// how the events actually get collected and stored. If you need to expose trace
-// events to some other universe, you can copy-and-paste this file as well as
-// trace_event.h, modifying the macros contained there as necessary for the
-// target platform. The end result is that multiple libraries can funnel events
-// through to a shared trace event collector.
-
-// IMPORTANT: To avoid conflicts, if you need to modify this file for a library,
-// land your change in base/ first, and then copy-and-paste it.
-
-// Trace events are for tracking application performance and resource usage.
-// Macros are provided to track:
-//    Begin and end of function calls
-//    Counters
-//
-// Events are issued against categories. Whereas LOG's
-// categories are statically defined, TRACE categories are created
-// implicitly with a string. For example:
-//   TRACE_EVENT_INSTANT0("MY_SUBSYSTEM", "SomeImportantEvent",
-//                        TRACE_EVENT_SCOPE_THREAD)
-//
-// It is often the case that one trace may belong in multiple categories at the
-// same time. The first argument to the trace can be a comma-separated list of
-// categories, forming a category group, like:
-//
-// TRACE_EVENT_INSTANT0("input,views", "OnMouseOver", TRACE_EVENT_SCOPE_THREAD)
-//
-// We can enable/disable tracing of OnMouseOver by enabling/disabling either
-// category.
-//
-// Events can be INSTANT, or can be pairs of BEGIN and END in the same scope:
-//   TRACE_EVENT_BEGIN0("MY_SUBSYSTEM", "SomethingCostly")
-//   doSomethingCostly()
-//   TRACE_EVENT_END0("MY_SUBSYSTEM", "SomethingCostly")
-// Note: our tools can't always determine the correct BEGIN/END pairs unless
-// these are used in the same scope. Use ASYNC_BEGIN/ASYNC_END macros if you
-// need them to be in separate scopes.
-//
-// A common use case is to trace entire function scopes. This
-// issues a trace BEGIN and END automatically:
-//   void doSomethingCostly() {
-//     TRACE_EVENT0("MY_SUBSYSTEM", "doSomethingCostly");
-//     ...
-//   }
-//
-// Additional parameters can be associated with an event:
-//   void doSomethingCostly2(int howMuch) {
-//     TRACE_EVENT1("MY_SUBSYSTEM", "doSomethingCostly",
-//         "howMuch", howMuch);
-//     ...
-//   }
-//
-// The trace system will automatically add to this information the
-// current process id, thread id, and a timestamp in microseconds.
-//
-// To trace an asynchronous procedure such as an IPC send/receive, use
-// ASYNC_BEGIN and ASYNC_END:
-//   [single threaded sender code]
-//     static int send_count = 0;
-//     ++send_count;
-//     TRACE_EVENT_ASYNC_BEGIN0("ipc", "message", send_count);
-//     Send(new MyMessage(send_count));
-//   [receive code]
-//     void OnMyMessage(send_count) {
-//       TRACE_EVENT_ASYNC_END0("ipc", "message", send_count);
-//     }
-// The third parameter is a unique ID to match ASYNC_BEGIN/ASYNC_END pairs.
-// ASYNC_BEGIN and ASYNC_END can occur on any thread of any traced process.
-// Pointers can be used for the ID parameter, and they will be mangled
-// internally so that the same pointer on two different processes will not
-// match. For example:
-//   class MyTracedClass {
-//    public:
-//     MyTracedClass() {
-//       TRACE_EVENT_ASYNC_BEGIN0("category", "MyTracedClass", this);
-//     }
-//     ~MyTracedClass() {
-//       TRACE_EVENT_ASYNC_END0("category", "MyTracedClass", this);
-//     }
-//   }
-//
-// Trace event also supports counters, which is a way to track a quantity
-// as it varies over time. Counters are created with the following macro:
-//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter", g_myCounterValue);
-//
-// Counters are process-specific. The macro itself can be issued from any
-// thread, however.
-//
-// Sometimes, you want to track two counters at once. You can do this with two
-// counter macros:
-//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter0", g_myCounterValue[0]);
-//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter1", g_myCounterValue[1]);
-// Or you can do it with a combined macro:
-//   TRACE_COUNTER2("MY_SUBSYSTEM", "myCounter",
-//       "bytesPinned", g_myCounterValue[0],
-//       "bytesAllocated", g_myCounterValue[1]);
-// This indicates to the tracing UI that these counters should be displayed
-// in a single graph, as a summed area chart.
-//
-// Since counters are in a global namespace, you may want to disambiguate with a
-// unique ID, by using the TRACE_COUNTER_ID* variations.
-//
-// By default, trace collection is compiled in, but turned off at runtime.
-// Collecting trace data is the responsibility of the embedding
-// application. In Chrome's case, navigating to about:tracing will turn on
-// tracing and display data collected across all active processes.
-//
-//
-// Memory scoping note:
-// Tracing copies the pointers, not the string content, of the strings passed
-// in for category_group, name, and arg_names.  Thus, the following code will
-// cause problems:
-//     char* str = strdup("importantName");
-//     TRACE_EVENT_INSTANT0("SUBSYSTEM", str);  // BAD!
-//     free(str);                   // Trace system now has dangling pointer
-//
-// To avoid this issue with the |name| and |arg_name| parameters, use the
-// TRACE_EVENT_COPY_XXX overloads of the macros at additional runtime overhead.
-// Notes: The category must always be in a long-lived char* (i.e. static const).
-//        The |arg_values|, when used, are always deep copied with the _COPY
-//        macros.
-//
-// When are string argument values copied:
-// const char* arg_values are only referenced by default:
-//     TRACE_EVENT1("category", "name",
-//                  "arg1", "literal string is only referenced");
-// Use TRACE_STR_COPY to force copying of a const char*:
-//     TRACE_EVENT1("category", "name",
-//                  "arg1", TRACE_STR_COPY("string will be copied"));
-// std::string arg_values are always copied:
-//     TRACE_EVENT1("category", "name",
-//                  "arg1", std::string("string will be copied"));
-//
-//
-// Convertable notes:
-// Converting a large data type to a string can be costly. To help with this,
-// the trace framework provides an interface ConvertableToTraceFormat. If you
-// inherit from it and implement the AppendAsTraceFormat method the trace
-// framework will call back to your object to convert a trace output time. This
-// means, if the category for the event is disabled, the conversion will not
-// happen.
-//
-//   class MyData : public base::trace_event::ConvertableToTraceFormat {
-//    public:
-//     MyData() {}
-//     void AppendAsTraceFormat(std::string* out) const override {
-//       out->append("{\"foo\":1}");
-//     }
-//    private:
-//     ~MyData() override {}
-//     DISALLOW_COPY_AND_ASSIGN(MyData);
-//   };
-//
-//   TRACE_EVENT1("foo", "bar", "data",
-//                std::unique_ptr<ConvertableToTraceFormat>(new MyData()));
-//
-// The trace framework will take ownership if the passed pointer and it will
-// be free'd when the trace buffer is flushed.
-//
-// Note, we only do the conversion when the buffer is flushed, so the provided
-// data object should not be modified after it's passed to the trace framework.
-//
-//
-// Thread Safety:
-// A thread safe singleton and mutex are used for thread safety. Category
-// enabled flags are used to limit the performance impact when the system
-// is not enabled.
-//
-// TRACE_EVENT macros first cache a pointer to a category. The categories are
-// statically allocated and safe at all times, even after exit. Fetching a
-// category is protected by the TraceLog::lock_. Multiple threads initializing
-// the static variable is safe, as they will be serialized by the lock and
-// multiple calls will return the same pointer to the category.
-//
-// Then the category_group_enabled flag is checked. This is a unsigned char, and
-// not intended to be multithread safe. It optimizes access to AddTraceEvent
-// which is threadsafe internally via TraceLog::lock_. The enabled flag may
-// cause some threads to incorrectly call or skip calling AddTraceEvent near
-// the time of the system being enabled or disabled. This is acceptable as
-// we tolerate some data loss while the system is being enabled/disabled and
-// because AddTraceEvent is threadsafe internally and checks the enabled state
-// again under lock.
-//
-// Without the use of these static category pointers and enabled flags all
-// trace points would carry a significant performance cost of acquiring a lock
-// and resolving the category.
-
-#if defined(TRACE_EVENT0)
-#error "Another copy of this file has already been included."
-#endif
-
-// This will mark the trace event as disabled by default. The user will need
-// to explicitly enable the event.
-#define TRACE_DISABLED_BY_DEFAULT(name) "disabled-by-default-" name
-
-// Records a pair of begin and end events called "name" for the current
-// scope, with 0, 1 or 2 associated arguments. If the category is not
-// enabled, then this does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_EVENT0(category_group, name)    \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name)
-#define TRACE_EVENT_WITH_FLOW0(category_group, name, bind_id, flow_flags)  \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id, \
-                                            flow_flags)
-#define TRACE_EVENT1(category_group, name, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val)
-#define TRACE_EVENT_WITH_FLOW1(category_group, name, bind_id, flow_flags,  \
-                               arg1_name, arg1_val)                        \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id, \
-                                            flow_flags, arg1_name, arg1_val)
-#define TRACE_EVENT2(category_group, name, arg1_name, arg1_val, arg2_name,   \
-                     arg2_val)                                               \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val, \
-                                  arg2_name, arg2_val)
-#define TRACE_EVENT_WITH_FLOW2(category_group, name, bind_id, flow_flags,    \
-                               arg1_name, arg1_val, arg2_name, arg2_val)     \
-  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id,   \
-                                            flow_flags, arg1_name, arg1_val, \
-                                            arg2_name, arg2_val)
-
-// UNSHIPPED_TRACE_EVENT* are like TRACE_EVENT* except that they are not
-// included in official builds.
-
-#if OFFICIAL_BUILD
-#undef TRACING_IS_OFFICIAL_BUILD
-#define TRACING_IS_OFFICIAL_BUILD 1
-#elif !defined(TRACING_IS_OFFICIAL_BUILD)
-#define TRACING_IS_OFFICIAL_BUILD 0
-#endif
-
-#if TRACING_IS_OFFICIAL_BUILD
-#define UNSHIPPED_TRACE_EVENT0(category_group, name) (void)0
-#define UNSHIPPED_TRACE_EVENT1(category_group, name, arg1_name, arg1_val) \
-  (void)0
-#define UNSHIPPED_TRACE_EVENT2(category_group, name, arg1_name, arg1_val, \
-                               arg2_name, arg2_val)                       \
-  (void)0
-#define UNSHIPPED_TRACE_EVENT_INSTANT0(category_group, name, scope) (void)0
-#define UNSHIPPED_TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, \
-                                       arg1_val)                               \
-  (void)0
-#define UNSHIPPED_TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, \
-                                       arg1_val, arg2_name, arg2_val)          \
-  (void)0
-#else
-#define UNSHIPPED_TRACE_EVENT0(category_group, name) \
-  TRACE_EVENT0(category_group, name)
-#define UNSHIPPED_TRACE_EVENT1(category_group, name, arg1_name, arg1_val) \
-  TRACE_EVENT1(category_group, name, arg1_name, arg1_val)
-#define UNSHIPPED_TRACE_EVENT2(category_group, name, arg1_name, arg1_val, \
-                               arg2_name, arg2_val)                       \
-  TRACE_EVENT2(category_group, name, arg1_name, arg1_val, arg2_name, arg2_val)
-#define UNSHIPPED_TRACE_EVENT_INSTANT0(category_group, name, scope) \
-  TRACE_EVENT_INSTANT0(category_group, name, scope)
-#define UNSHIPPED_TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, \
-                                       arg1_val)                               \
-  TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, arg1_val)
-#define UNSHIPPED_TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, \
-                                       arg1_val, arg2_name, arg2_val)          \
-  TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, arg1_val,       \
-                       arg2_name, arg2_val)
-#endif
-
-// Records a single event called "name" immediately, with 0, 1 or 2
-// associated arguments. If the category is not enabled, then this
-// does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_EVENT_INSTANT0(category_group, name, scope)                   \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE | scope)
-#define TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
-                           TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val)
-#define TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, arg1_val, \
-                             arg2_name, arg2_val)                              \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
-                           TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val, \
-                           arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_INSTANT0(category_group, name, scope)              \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY | scope)
-#define TRACE_EVENT_COPY_INSTANT1(category_group, name, scope, arg1_name,   \
-                                  arg1_val)                                 \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_INSTANT2(category_group, name, scope, arg1_name,      \
-                                  arg1_val, arg2_name, arg2_val)               \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
-                           TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val, \
-                           arg2_name, arg2_val)
-
-#define TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(category_group, name, scope, \
-                                            timestamp)                   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                    \
-      TRACE_EVENT_PHASE_INSTANT, category_group, name, 0, 0, timestamp,  \
-      TRACE_EVENT_FLAG_NONE | scope)
-
-// Syntactic sugars for the sampling tracing in the main thread.
-#define TRACE_EVENT_SCOPED_SAMPLING_STATE(category, name) \
-  TRACE_EVENT_SCOPED_SAMPLING_STATE_FOR_BUCKET(0, category, name)
-#define TRACE_EVENT_GET_SAMPLING_STATE() \
-  TRACE_EVENT_GET_SAMPLING_STATE_FOR_BUCKET(0)
-#define TRACE_EVENT_SET_SAMPLING_STATE(category, name) \
-  TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(0, category, name)
-#define TRACE_EVENT_SET_NONCONST_SAMPLING_STATE(categoryAndName) \
-  TRACE_EVENT_SET_NONCONST_SAMPLING_STATE_FOR_BUCKET(0, categoryAndName)
-
-// Records a single BEGIN event called "name" immediately, with 0, 1 or 2
-// associated arguments. If the category is not enabled, then this
-// does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_EVENT_BEGIN0(category_group, name)                          \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_BEGIN1(category_group, name, arg1_name, arg1_val)     \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_BEGIN2(category_group, name, arg1_name, arg1_val,     \
-                           arg2_name, arg2_val)                           \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val,    \
-                           arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_BEGIN0(category_group, name)                     \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_BEGIN1(category_group, name, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name,  \
-                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_BEGIN2(category_group, name, arg1_name, arg1_val, \
-                                arg2_name, arg2_val)                       \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name,  \
-                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,     \
-                           arg2_name, arg2_val)
-
-// Similar to TRACE_EVENT_BEGINx but with a custom |at| timestamp provided.
-// - |id| is used to match the _BEGIN event with the _END event.
-//   Events are considered to match if their category_group, name and id values
-//   all match. |id| must either be a pointer or an integer value up to 64 bits.
-//   If it's a pointer, the bits will be xored with a hash of the process ID so
-//   that the same pointer on two different processes will not collide.
-#define TRACE_EVENT_BEGIN_WITH_ID_TID_AND_TIMESTAMP0(category_group, name, id, \
-                                                     thread_id, timestamp)     \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id,      \
-      timestamp, TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP0(                \
-    category_group, name, id, thread_id, timestamp)                       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
-      timestamp, TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP1(                \
-    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val)  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
-      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP2(                \
-    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val,  \
-    arg2_name, arg2_val)                                                  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
-      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,   \
-      arg2_val)
-
-// Records a single END event for "name" immediately. If the category
-// is not enabled, then this does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_EVENT_END0(category_group, name)                          \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_END1(category_group, name, arg1_name, arg1_val)     \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_END2(category_group, name, arg1_name, arg1_val, arg2_name, \
-                         arg2_val)                                             \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,        \
-                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val,         \
-                           arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_END0(category_group, name)                     \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_END1(category_group, name, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,  \
-                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_END2(category_group, name, arg1_name, arg1_val, \
-                              arg2_name, arg2_val)                       \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,  \
-                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,   \
-                           arg2_name, arg2_val)
-
-#define TRACE_EVENT_MARK_WITH_TIMESTAMP1(category_group, name, timestamp, \
-                                         arg1_name, arg1_val)             \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
-      TRACE_EVENT_PHASE_MARK, category_group, name, 0, 0, timestamp,      \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-
-#define TRACE_EVENT_COPY_MARK(category_group, name)                      \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_MARK, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY)
-
-#define TRACE_EVENT_COPY_MARK_WITH_TIMESTAMP(category_group, name, timestamp) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
-      TRACE_EVENT_PHASE_MARK, category_group, name, 0, 0, timestamp,          \
-      TRACE_EVENT_FLAG_COPY)
-
-// Similar to TRACE_EVENT_ENDx but with a custom |at| timestamp provided.
-// - |id| is used to match the _BEGIN event with the _END event.
-//   Events are considered to match if their category_group, name and id values
-//   all match. |id| must either be a pointer or an integer value up to 64 bits.
-//   If it's a pointer, the bits will be xored with a hash of the process ID so
-//   that the same pointer on two different processes will not collide.
-#define TRACE_EVENT_END_WITH_ID_TID_AND_TIMESTAMP0(category_group, name, id, \
-                                                   thread_id, timestamp)     \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                        \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,      \
-      timestamp, TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP0(                \
-    category_group, name, id, thread_id, timestamp)                     \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id, \
-      timestamp, TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP1(                 \
-    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                    \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,  \
-      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP2(                 \
-    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val, \
-    arg2_name, arg2_val)                                                 \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                    \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,  \
-      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,  \
-      arg2_val)
-
-// Records the value of a counter called "name" immediately. Value
-// must be representable as a 32 bit integer.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_COUNTER1(category_group, name, value)                         \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE, "value",                  \
-                           static_cast<int>(value))
-#define TRACE_COPY_COUNTER1(category_group, name, value)                    \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY, "value",                  \
-                           static_cast<int>(value))
-
-// Records the values of a multi-parted counter called "name" immediately.
-// The UI will treat value1 and value2 as parts of a whole, displaying their
-// values as a stacked-bar chart.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-#define TRACE_COUNTER2(category_group, name, value1_name, value1_val,       \
-                       value2_name, value2_val)                             \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
-                           TRACE_EVENT_FLAG_NONE, value1_name,              \
-                           static_cast<int>(value1_val), value2_name,       \
-                           static_cast<int>(value2_val))
-#define TRACE_COPY_COUNTER2(category_group, name, value1_name, value1_val,  \
-                            value2_name, value2_val)                        \
-  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
-                           TRACE_EVENT_FLAG_COPY, value1_name,              \
-                           static_cast<int>(value1_val), value2_name,       \
-                           static_cast<int>(value2_val))
-
-// Similar to TRACE_COUNTERx, but with a custom |timestamp| provided.
-#define TRACE_COUNTER_WITH_TIMESTAMP1(category_group, name, timestamp, value) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                    \
-      TRACE_EVENT_PHASE_COUNTER, category_group, name, timestamp,             \
-      TRACE_EVENT_FLAG_NONE, "value", static_cast<int>(value))
-
-#define TRACE_COUNTER_WITH_TIMESTAMP2(category_group, name, timestamp,      \
-                                      value1_name, value1_val, value2_name, \
-                                      value2_val)                           \
-  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                  \
-      TRACE_EVENT_PHASE_COUNTER, category_group, name, timestamp,           \
-      TRACE_EVENT_FLAG_NONE, value1_name, static_cast<int>(value1_val),     \
-      value2_name, static_cast<int>(value2_val))
-
-// Records the value of a counter called "name" immediately. Value
-// must be representable as a 32 bit integer.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-// - |id| is used to disambiguate counters with the same name. It must either
-//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
-//   will be xored with a hash of the process ID so that the same pointer on
-//   two different processes will not collide.
-#define TRACE_COUNTER_ID1(category_group, name, id, value)                    \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_NONE, "value",  \
-                                   static_cast<int>(value))
-#define TRACE_COPY_COUNTER_ID1(category_group, name, id, value)               \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_COPY, "value",  \
-                                   static_cast<int>(value))
-
-// Records the values of a multi-parted counter called "name" immediately.
-// The UI will treat value1 and value2 as parts of a whole, displaying their
-// values as a stacked-bar chart.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-// - |id| is used to disambiguate counters with the same name. It must either
-//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
-//   will be xored with a hash of the process ID so that the same pointer on
-//   two different processes will not collide.
-#define TRACE_COUNTER_ID2(category_group, name, id, value1_name, value1_val,  \
-                          value2_name, value2_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_NONE,           \
-                                   value1_name, static_cast<int>(value1_val), \
-                                   value2_name, static_cast<int>(value2_val))
-#define TRACE_COPY_COUNTER_ID2(category_group, name, id, value1_name,         \
-                               value1_val, value2_name, value2_val)           \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_COPY,           \
-                                   value1_name, static_cast<int>(value1_val), \
-                                   value2_name, static_cast<int>(value2_val))
-
-// TRACE_EVENT_SAMPLE_* events are injected by the sampling profiler.
-#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP0(category_group, name,       \
-                                                   thread_id, timestamp)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
-      TRACE_EVENT_FLAG_NONE)
-
-#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP1(                            \
-    category_group, name, thread_id, timestamp, arg1_name, arg1_val)           \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-
-#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP2(category_group, name,       \
-                                                   thread_id, timestamp,       \
-                                                   arg1_name, arg1_val,        \
-                                                   arg2_name, arg2_val)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// ASYNC_STEP_* APIs should be only used by legacy code. New code should
-// consider using NESTABLE_ASYNC_* APIs to describe substeps within an async
-// event.
-// Records a single ASYNC_BEGIN event called "name" immediately, with 0, 1 or 2
-// associated arguments. If the category is not enabled, then this
-// does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-// - |id| is used to match the ASYNC_BEGIN event with the ASYNC_END event. ASYNC
-//   events are considered to match if their category_group, name and id values
-//   all match. |id| must either be a pointer or an integer value up to 64 bits.
-//   If it's a pointer, the bits will be xored with a hash of the process ID so
-//   that the same pointer on two different processes will not collide.
-//
-// An asynchronous operation can consist of multiple phases. The first phase is
-// defined by the ASYNC_BEGIN calls. Additional phases can be defined using the
-// ASYNC_STEP_INTO or ASYNC_STEP_PAST macros. The ASYNC_STEP_INTO macro will
-// annotate the block following the call. The ASYNC_STEP_PAST macro will
-// annotate the block prior to the call. Note that any particular event must use
-// only STEP_INTO or STEP_PAST macros; they can not mix and match. When the
-// operation completes, call ASYNC_END.
-//
-// An ASYNC trace typically occurs on a single thread (if not, they will only be
-// drawn on the thread defined in the ASYNC_BEGIN event), but all events in that
-// operation must use the same |name| and |id|. Each step can have its own
-// args.
-#define TRACE_EVENT_ASYNC_BEGIN0(category_group, name, id)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
-                                   category_group, name, id,      \
-                                   TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
-                                 arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,     \
-                                   category_group, name, id,          \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
-                                 arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,        \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_ASYNC_BEGIN0(category_group, name, id)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
-                                   category_group, name, id,      \
-                                   TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
-                                      arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,          \
-                                   category_group, name, id,               \
-                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
-                                      arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                        \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,             \
-      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// Similar to TRACE_EVENT_ASYNC_BEGINx but with a custom |at| timestamp
-// provided.
-#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, id, \
-                                                timestamp)                \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,            \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP1(                           \
-    category_group, name, id, timestamp, arg1_name, arg1_val)              \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                      \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,             \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE, \
-      arg1_name, arg1_val)
-#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP2(category_group, name, id,      \
-                                                timestamp, arg1_name,          \
-                                                arg1_val, arg2_name, arg2_val) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,                 \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,     \
-      arg1_name, arg1_val, arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, id, \
-                                                     timestamp)                \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,                 \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
-
-// Records a single ASYNC_STEP_INTO event for |step| immediately. If the
-// category is not enabled, then this does nothing. The |name| and |id| must
-// match the ASYNC_BEGIN event above. The |step| param identifies this step
-// within the async event. This should be called at the beginning of the next
-// phase of an asynchronous operation. The ASYNC_BEGIN event must not have any
-// ASYNC_STEP_PAST events.
-#define TRACE_EVENT_ASYNC_STEP_INTO0(category_group, name, id, step)  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP_INTO, \
-                                   category_group, name, id,          \
-                                   TRACE_EVENT_FLAG_NONE, "step", step)
-#define TRACE_EVENT_ASYNC_STEP_INTO1(category_group, name, id, step, \
-                                     arg1_name, arg1_val)            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
-      TRACE_EVENT_PHASE_ASYNC_STEP_INTO, category_group, name, id,   \
-      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
-
-// Similar to TRACE_EVENT_ASYNC_STEP_INTOx but with a custom |at| timestamp
-// provided.
-#define TRACE_EVENT_ASYNC_STEP_INTO_WITH_TIMESTAMP0(category_group, name, id, \
-                                                    step, timestamp)          \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
-      TRACE_EVENT_PHASE_ASYNC_STEP_INTO, category_group, name, id,            \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
-      "step", step)
-
-// Records a single ASYNC_STEP_PAST event for |step| immediately. If the
-// category is not enabled, then this does nothing. The |name| and |id| must
-// match the ASYNC_BEGIN event above. The |step| param identifies this step
-// within the async event. This should be called at the beginning of the next
-// phase of an asynchronous operation. The ASYNC_BEGIN event must not have any
-// ASYNC_STEP_INTO events.
-#define TRACE_EVENT_ASYNC_STEP_PAST0(category_group, name, id, step)  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP_PAST, \
-                                   category_group, name, id,          \
-                                   TRACE_EVENT_FLAG_NONE, "step", step)
-#define TRACE_EVENT_ASYNC_STEP_PAST1(category_group, name, id, step, \
-                                     arg1_name, arg1_val)            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
-      TRACE_EVENT_PHASE_ASYNC_STEP_PAST, category_group, name, id,   \
-      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
-
-// Records a single ASYNC_END event for "name" immediately. If the category
-// is not enabled, then this does nothing.
-#define TRACE_EVENT_ASYNC_END0(category_group, name, id)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
-                                   category_group, name, id,    \
-                                   TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_ASYNC_END1(category_group, name, id, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,               \
-                                   category_group, name, id,                  \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_ASYNC_END2(category_group, name, id, arg1_name, arg1_val, \
-                               arg2_name, arg2_val)                           \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                           \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_ASYNC_END0(category_group, name, id)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
-                                   category_group, name, id,    \
-                                   TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_ASYNC_END1(category_group, name, id, arg1_name, \
-                                    arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,          \
-                                   category_group, name, id,             \
-                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_ASYNC_END2(category_group, name, id, arg1_name, \
-                                    arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                      \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,             \
-      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// Similar to TRACE_EVENT_ASYNC_ENDx but with a custom |at| timestamp provided.
-#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP0(category_group, name, id, \
-                                              timestamp)                \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,            \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP1(category_group, name, id,       \
-                                              timestamp, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
-      arg1_name, arg1_val)
-#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP2(category_group, name, id,       \
-                                              timestamp, arg1_name, arg1_val, \
-                                              arg2_name, arg2_val)            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
-      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
-      arg1_name, arg1_val, arg2_name, arg2_val)
-
-// NESTABLE_ASYNC_* APIs are used to describe an async operation, which can
-// be nested within a NESTABLE_ASYNC event and/or have inner NESTABLE_ASYNC
-// events.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-// - A pair of NESTABLE_ASYNC_BEGIN event and NESTABLE_ASYNC_END event is
-//   considered as a match if their category_group, name and id all match.
-// - |id| must either be a pointer or an integer value up to 64 bits.
-//   If it's a pointer, the bits will be xored with a hash of the process ID so
-//   that the same pointer on two different processes will not collide.
-// - |id| is used to match a child NESTABLE_ASYNC event with its parent
-//   NESTABLE_ASYNC event. Therefore, events in the same nested event tree must
-//   be logged using the same id and category_group.
-//
-// Unmatched NESTABLE_ASYNC_END event will be parsed as an event that starts
-// at the first NESTABLE_ASYNC event of that id, and unmatched
-// NESTABLE_ASYNC_BEGIN event will be parsed as an event that ends at the last
-// NESTABLE_ASYNC event of that id. Corresponding warning messages for
-// unmatched events will be shown in the analysis view.
-
-// Records a single NESTABLE_ASYNC_BEGIN event called "name" immediately, with
-// 0, 1 or 2 associated arguments. If the category is not enabled, then this
-// does nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN0(category_group, name, id)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, \
-                                   category_group, name, id,               \
-                                   TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
-                                          arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN,     \
-                                   category_group, name, id,                   \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
-                                          arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-// Records a single NESTABLE_ASYNC_END event called "name" immediately, with 0
-// or 2 associated arguments. If the category is not enabled, then this does
-// nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_END0(category_group, name, id)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, \
-                                   category_group, name, id,             \
-                                   TRACE_EVENT_FLAG_NONE)
-// Records a single NESTABLE_ASYNC_END event called "name" immediately, with 1
-// associated argument. If the category is not enabled, then this does nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_END1(category_group, name, id, arg1_name, \
-                                        arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_END,     \
-                                   category_group, name, id,                 \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_NESTABLE_ASYNC_END2(category_group, name, id, arg1_name, \
-                                        arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                          \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,        \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// Records a single NESTABLE_ASYNC_INSTANT event called "name" immediately,
-// with one associated argument. If the category is not enabled, then this
-// does nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT1(category_group, name, id,        \
-                                            arg1_name, arg1_val)             \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, \
-                                   category_group, name, id,                 \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-// Records a single NESTABLE_ASYNC_INSTANT event called "name" immediately,
-// with 2 associated arguments. If the category is not enabled, then this
-// does nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT2(                              \
-    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, category_group, name, id, \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-
-#define TRACE_EVENT_COPY_NESTABLE_ASYNC_BEGIN_WITH_TTS2(                       \
-    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
-      TRACE_EVENT_FLAG_ASYNC_TTS | TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
-      arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_NESTABLE_ASYNC_END_WITH_TTS2(                         \
-    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,          \
-      TRACE_EVENT_FLAG_ASYNC_TTS | TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
-      arg2_name, arg2_val)
-
-// Similar to TRACE_EVENT_NESTABLE_ASYNC_{BEGIN,END}x but with a custom
-// |timestamp| provided.
-#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, \
-                                                         id, timestamp)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
-
-#define TRACE_EVENT_NESTABLE_ASYNC_END_WITH_TIMESTAMP0(category_group, name, \
-                                                       id, timestamp)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                        \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,        \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
-
-#define TRACE_EVENT_COPY_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP0(          \
-    category_group, name, id, timestamp)                                \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id, \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_NESTABLE_ASYNC_END_WITH_TIMESTAMP0(          \
-    category_group, name, id, timestamp)                              \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                 \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id, \
-      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
-
-// Records a single NESTABLE_ASYNC_INSTANT event called "name" immediately,
-// with 2 associated arguments. If the category is not enabled, then this
-// does nothing.
-#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT2(                              \
-    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
-      TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, category_group, name, id, \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// Records a single FLOW_BEGIN event called "name" immediately, with 0, 1 or 2
-// associated arguments. If the category is not enabled, then this
-// does nothing.
-// - category and name strings must have application lifetime (statics or
-//   literals). They may not include " chars.
-// - |id| is used to match the FLOW_BEGIN event with the FLOW_END event. FLOW
-//   events are considered to match if their category_group, name and id values
-//   all match. |id| must either be a pointer or an integer value up to 64 bits.
-//   If it's a pointer, the bits will be xored with a hash of the process ID so
-//   that the same pointer on two different processes will not collide.
-// FLOW events are different from ASYNC events in how they are drawn by the
-// tracing UI. A FLOW defines asynchronous data flow, such as posting a task
-// (FLOW_BEGIN) and later executing that task (FLOW_END). Expect FLOWs to be
-// drawn as lines or arrows from FLOW_BEGIN scopes to FLOW_END scopes. Similar
-// to ASYNC, a FLOW can consist of multiple phases. The first phase is defined
-// by the FLOW_BEGIN calls. Additional phases can be defined using the FLOW_STEP
-// macros. When the operation completes, call FLOW_END. An async operation can
-// span threads and processes, but all events in that operation must use the
-// same |name| and |id|. Each event can have its own args.
-#define TRACE_EVENT_FLOW_BEGIN0(category_group, name, id)        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
-                                   category_group, name, id,     \
-                                   TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_FLOW_BEGIN1(category_group, name, id, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,               \
-                                   category_group, name, id,                   \
-                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
-#define TRACE_EVENT_FLOW_BEGIN2(category_group, name, id, arg1_name, arg1_val, \
-                                arg2_name, arg2_val)                           \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
-      TRACE_EVENT_PHASE_FLOW_BEGIN, category_group, name, id,                  \
-      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_FLOW_BEGIN0(category_group, name, id)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
-                                   category_group, name, id,     \
-                                   TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_FLOW_BEGIN1(category_group, name, id, arg1_name, \
-                                     arg1_val)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,          \
-                                   category_group, name, id,              \
-                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_FLOW_BEGIN2(category_group, name, id, arg1_name, \
-                                     arg1_val, arg2_name, arg2_val)       \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
-      TRACE_EVENT_PHASE_FLOW_BEGIN, category_group, name, id,             \
-      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
-
-// Records a single FLOW_STEP event for |step| immediately. If the category
-// is not enabled, then this does nothing. The |name| and |id| must match the
-// FLOW_BEGIN event above. The |step| param identifies this step within the
-// async event. This should be called at the beginning of the next phase of an
-// asynchronous operation.
-#define TRACE_EVENT_FLOW_STEP0(category_group, name, id, step)  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
-                                   category_group, name, id,    \
-                                   TRACE_EVENT_FLAG_NONE, "step", step)
-#define TRACE_EVENT_FLOW_STEP1(category_group, name, id, step, arg1_name, \
-                               arg1_val)                                  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
-      TRACE_EVENT_PHASE_FLOW_STEP, category_group, name, id,              \
-      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
-#define TRACE_EVENT_COPY_FLOW_STEP0(category_group, name, id, step) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP,     \
-                                   category_group, name, id,        \
-                                   TRACE_EVENT_FLAG_COPY, "step", step)
-#define TRACE_EVENT_COPY_FLOW_STEP1(category_group, name, id, step, arg1_name, \
-                                    arg1_val)                                  \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
-      TRACE_EVENT_PHASE_FLOW_STEP, category_group, name, id,                   \
-      TRACE_EVENT_FLAG_COPY, "step", step, arg1_name, arg1_val)
-
-// Records a single FLOW_END event for "name" immediately. If the category
-// is not enabled, then this does nothing.
-#define TRACE_EVENT_FLOW_END0(category_group, name, id)                        \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_FLOW_END_BIND_TO_ENCLOSING0(category_group, name, id)      \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id,                                   \
-                                   TRACE_EVENT_FLAG_BIND_TO_ENCLOSING)
-#define TRACE_EVENT_FLOW_END1(category_group, name, id, arg1_name, arg1_val)   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
-                                   arg1_val)
-#define TRACE_EVENT_FLOW_END2(category_group, name, id, arg1_name, arg1_val,   \
-                              arg2_name, arg2_val)                             \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
-                                   arg1_val, arg2_name, arg2_val)
-#define TRACE_EVENT_COPY_FLOW_END0(category_group, name, id)                   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_COPY)
-#define TRACE_EVENT_COPY_FLOW_END1(category_group, name, id, arg1_name,        \
-                                   arg1_val)                                   \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
-                                   arg1_val)
-#define TRACE_EVENT_COPY_FLOW_END2(category_group, name, id, arg1_name,        \
-                                   arg1_val, arg2_name, arg2_val)              \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
-                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
-                                   arg1_val, arg2_name, arg2_val)
-
-// Special trace event macro to trace task execution with the location where it
-// was posted from.
-#define TRACE_TASK_EXECUTION(run_function, task) \
-  INTERNAL_TRACE_TASK_EXECUTION(run_function, task)
-
-// TRACE_EVENT_METADATA* events are information related to other
-// injected events, not events in their own right.
-#define TRACE_EVENT_METADATA1(category_group, name, arg1_name, arg1_val) \
-  INTERNAL_TRACE_EVENT_METADATA_ADD(category_group, name, arg1_name, arg1_val)
-
-// Records a clock sync event.
-#define TRACE_EVENT_CLOCK_SYNC_RECEIVER(sync_id)                               \
-  INTERNAL_TRACE_EVENT_ADD(                                                    \
-      TRACE_EVENT_PHASE_CLOCK_SYNC, "__metadata", "clock_sync",                \
-      TRACE_EVENT_FLAG_NONE, "sync_id", sync_id)
-#define TRACE_EVENT_CLOCK_SYNC_ISSUER(sync_id, issue_ts, issue_end_ts)         \
-  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                     \
-      TRACE_EVENT_PHASE_CLOCK_SYNC, "__metadata", "clock_sync",                \
-      issue_end_ts.ToInternalValue(), TRACE_EVENT_FLAG_NONE,                   \
-      "sync_id", sync_id, "issue_ts", issue_ts.ToInternalValue())
-
-// Macros to track the life time and value of arbitrary client objects.
-// See also TraceTrackableObject.
-#define TRACE_EVENT_OBJECT_CREATED_WITH_ID(category_group, name, id) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
-      TRACE_EVENT_PHASE_CREATE_OBJECT, category_group, name,         \
-      TRACE_ID_DONT_MANGLE(id), TRACE_EVENT_FLAG_NONE)
-
-#define TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID(category_group, name, id, \
-                                            snapshot)                 \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
-      TRACE_EVENT_PHASE_SNAPSHOT_OBJECT, category_group, name,        \
-      TRACE_ID_DONT_MANGLE(id), TRACE_EVENT_FLAG_NONE, "snapshot", snapshot)
-
-#define TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID_AND_TIMESTAMP(                    \
-    category_group, name, id, timestamp, snapshot)                            \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
-      TRACE_EVENT_PHASE_SNAPSHOT_OBJECT, category_group, name,                \
-      TRACE_ID_DONT_MANGLE(id), TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, \
-      TRACE_EVENT_FLAG_NONE, "snapshot", snapshot)
-
-#define TRACE_EVENT_OBJECT_DELETED_WITH_ID(category_group, name, id) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
-      TRACE_EVENT_PHASE_DELETE_OBJECT, category_group, name,         \
-      TRACE_ID_DONT_MANGLE(id), TRACE_EVENT_FLAG_NONE)
-
-// Records entering and leaving trace event contexts. |category_group| and
-// |name| specify the context category and type. |context| is a
-// snapshotted context object id.
-#define TRACE_EVENT_ENTER_CONTEXT(category_group, name, context) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                              \
-      TRACE_EVENT_PHASE_ENTER_CONTEXT, category_group, name,     \
-      TRACE_ID_DONT_MANGLE(context), TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_LEAVE_CONTEXT(category_group, name, context) \
-  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                              \
-      TRACE_EVENT_PHASE_LEAVE_CONTEXT, category_group, name,     \
-      TRACE_ID_DONT_MANGLE(context), TRACE_EVENT_FLAG_NONE)
-#define TRACE_EVENT_SCOPED_CONTEXT(category_group, name, context) \
-  INTERNAL_TRACE_EVENT_SCOPED_CONTEXT(category_group, name,       \
-                                      TRACE_ID_DONT_MANGLE(context))
-
-// Macro to specify that two trace IDs are identical. For example,
-// TRACE_BIND_IDS(
-//     "category", "name",
-//     TRACE_ID_WITH_SCOPE("net::URLRequest", 0x1000),
-//     TRACE_ID_WITH_SCOPE("blink::ResourceFetcher::FetchRequest", 0x2000))
-// tells the trace consumer that events with ID ("net::URLRequest", 0x1000) from
-// the current process have the same ID as events with ID
-// ("blink::ResourceFetcher::FetchRequest", 0x2000).
-#define TRACE_BIND_IDS(category_group, name, id, bind_id) \
-  INTERNAL_TRACE_EVENT_ADD_BIND_IDS(category_group, name, id, bind_id);
-
-// Macro to efficiently determine if a given category group is enabled.
-#define TRACE_EVENT_CATEGORY_GROUP_ENABLED(category_group, ret)             \
-  do {                                                                      \
-    INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group);                 \
-    if (INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE()) { \
-      *ret = true;                                                          \
-    } else {                                                                \
-      *ret = false;                                                         \
-    }                                                                       \
-  } while (0)
-
-// Macro to explicitly warm up a given category group. This could be useful in
-// cases where we want to initialize a category group before any trace events
-// for that category group is reported. For example, to have a category group
-// always show up in the "record categories" list for manually selecting
-// settings in about://tracing.
-#define TRACE_EVENT_WARMUP_CATEGORY(category_group) \
-  INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group)
-
-// Macro to efficiently determine, through polling, if a new trace has begun.
-#define TRACE_EVENT_IS_NEW_TRACE(ret)                                      \
-  do {                                                                     \
-    static int INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = 0;          \
-    int num_traces_recorded = TRACE_EVENT_API_GET_NUM_TRACES_RECORDED();   \
-    if (num_traces_recorded != -1 &&                                       \
-        num_traces_recorded !=                                             \
-            INTERNAL_TRACE_EVENT_UID(lastRecordingNumber)) {               \
-      INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = num_traces_recorded; \
-      *ret = true;                                                         \
-    } else {                                                               \
-      *ret = false;                                                        \
-    }                                                                      \
-  } while (0)
-
-// Notes regarding the following definitions:
-// New values can be added and propagated to third party libraries, but existing
-// definitions must never be changed, because third party libraries may use old
-// definitions.
-
-// Phase indicates the nature of an event entry. E.g. part of a begin/end pair.
-#define TRACE_EVENT_PHASE_BEGIN ('B')
-#define TRACE_EVENT_PHASE_END ('E')
-#define TRACE_EVENT_PHASE_COMPLETE ('X')
-#define TRACE_EVENT_PHASE_INSTANT ('I')
-#define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S')
-#define TRACE_EVENT_PHASE_ASYNC_STEP_INTO ('T')
-#define TRACE_EVENT_PHASE_ASYNC_STEP_PAST ('p')
-#define TRACE_EVENT_PHASE_ASYNC_END ('F')
-#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN ('b')
-#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_END ('e')
-#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT ('n')
-#define TRACE_EVENT_PHASE_FLOW_BEGIN ('s')
-#define TRACE_EVENT_PHASE_FLOW_STEP ('t')
-#define TRACE_EVENT_PHASE_FLOW_END ('f')
-#define TRACE_EVENT_PHASE_METADATA ('M')
-#define TRACE_EVENT_PHASE_COUNTER ('C')
-#define TRACE_EVENT_PHASE_SAMPLE ('P')
-#define TRACE_EVENT_PHASE_CREATE_OBJECT ('N')
-#define TRACE_EVENT_PHASE_SNAPSHOT_OBJECT ('O')
-#define TRACE_EVENT_PHASE_DELETE_OBJECT ('D')
-#define TRACE_EVENT_PHASE_MEMORY_DUMP ('v')
-#define TRACE_EVENT_PHASE_MARK ('R')
-#define TRACE_EVENT_PHASE_CLOCK_SYNC ('c')
-#define TRACE_EVENT_PHASE_ENTER_CONTEXT ('(')
-#define TRACE_EVENT_PHASE_LEAVE_CONTEXT (')')
-#define TRACE_EVENT_PHASE_BIND_IDS ('=')
-
-// Flags for changing the behavior of TRACE_EVENT_API_ADD_TRACE_EVENT.
-#define TRACE_EVENT_FLAG_NONE (static_cast<unsigned int>(0))
-#define TRACE_EVENT_FLAG_COPY (static_cast<unsigned int>(1 << 0))
-#define TRACE_EVENT_FLAG_HAS_ID (static_cast<unsigned int>(1 << 1))
-#define TRACE_EVENT_FLAG_MANGLE_ID (static_cast<unsigned int>(1 << 2))
-#define TRACE_EVENT_FLAG_SCOPE_OFFSET (static_cast<unsigned int>(1 << 3))
-#define TRACE_EVENT_FLAG_SCOPE_EXTRA (static_cast<unsigned int>(1 << 4))
-#define TRACE_EVENT_FLAG_EXPLICIT_TIMESTAMP (static_cast<unsigned int>(1 << 5))
-#define TRACE_EVENT_FLAG_ASYNC_TTS (static_cast<unsigned int>(1 << 6))
-#define TRACE_EVENT_FLAG_BIND_TO_ENCLOSING (static_cast<unsigned int>(1 << 7))
-#define TRACE_EVENT_FLAG_FLOW_IN (static_cast<unsigned int>(1 << 8))
-#define TRACE_EVENT_FLAG_FLOW_OUT (static_cast<unsigned int>(1 << 9))
-#define TRACE_EVENT_FLAG_HAS_CONTEXT_ID (static_cast<unsigned int>(1 << 10))
-#define TRACE_EVENT_FLAG_HAS_PROCESS_ID (static_cast<unsigned int>(1 << 11))
-
-#define TRACE_EVENT_FLAG_SCOPE_MASK                          \
-  (static_cast<unsigned int>(TRACE_EVENT_FLAG_SCOPE_OFFSET | \
-                             TRACE_EVENT_FLAG_SCOPE_EXTRA))
-
-// Type values for identifying types in the TraceValue union.
-#define TRACE_VALUE_TYPE_BOOL (static_cast<unsigned char>(1))
-#define TRACE_VALUE_TYPE_UINT (static_cast<unsigned char>(2))
-#define TRACE_VALUE_TYPE_INT (static_cast<unsigned char>(3))
-#define TRACE_VALUE_TYPE_DOUBLE (static_cast<unsigned char>(4))
-#define TRACE_VALUE_TYPE_POINTER (static_cast<unsigned char>(5))
-#define TRACE_VALUE_TYPE_STRING (static_cast<unsigned char>(6))
-#define TRACE_VALUE_TYPE_COPY_STRING (static_cast<unsigned char>(7))
-#define TRACE_VALUE_TYPE_CONVERTABLE (static_cast<unsigned char>(8))
-
-// Enum reflecting the scope of an INSTANT event. Must fit within
-// TRACE_EVENT_FLAG_SCOPE_MASK.
-#define TRACE_EVENT_SCOPE_GLOBAL (static_cast<unsigned char>(0 << 3))
-#define TRACE_EVENT_SCOPE_PROCESS (static_cast<unsigned char>(1 << 3))
-#define TRACE_EVENT_SCOPE_THREAD (static_cast<unsigned char>(2 << 3))
-
-#define TRACE_EVENT_SCOPE_NAME_GLOBAL ('g')
-#define TRACE_EVENT_SCOPE_NAME_PROCESS ('p')
-#define TRACE_EVENT_SCOPE_NAME_THREAD ('t')
-
 
 // The pointer returned from GetCategoryGroupEnabled() points to a
 // value with zero or more of the following bits. Used in this class only.
@@ -1161,34 +44,7 @@ enum CategoryGroupEnabledFlags {
 // By default, trace IDs are eventually converted to a single 64-bit number. Use
 // this macro to add a scope string.
 #define TRACE_ID_WITH_SCOPE(scope, id) \
-  node::tracing::TraceID::WithScope(scope, id)
-
-// Sets the current sample state to the given category and name (both must be
-// constant strings). These states are intended for a sampling profiler.
-// Implementation note: we store category and name together because we don't
-// want the inconsistency/expense of storing two pointers.
-// |thread_bucket| is [0..2] and is used to statically isolate samples in one
-// thread from others.
-#define TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(bucket_number, category, \
-                                                  name)                    \
-  node::tracing::TraceEventSamplingStateScope<bucket_number>::Set( \
-      category "\0" name)
-
-// Returns a current sampling state of the given bucket.
-#define TRACE_EVENT_GET_SAMPLING_STATE_FOR_BUCKET(bucket_number) \
-  node::tracing::TraceEventSamplingStateScope<bucket_number>::Current()
-
-// Creates a scope of a sampling state of the given bucket.
-//
-// {  // The sampling state is set within this scope.
-//    TRACE_EVENT_SAMPLING_STATE_SCOPE_FOR_BUCKET(0, "category", "name");
-//    ...;
-// }
-#define TRACE_EVENT_SCOPED_SAMPLING_STATE_FOR_BUCKET(bucket_number, category, \
-                                                     name)                    \
-  node::tracing::TraceEventSamplingStateScope<bucket_number>                   \
-      traceEventSamplingScope(category "\0" name);
-
+  trace_event_internal::TraceID::WithScope(scope, id)
 
 #define INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE() \
   *INTERNAL_TRACE_EVENT_UID(category_group_enabled) &                    \
@@ -1235,8 +91,7 @@ enum CategoryGroupEnabledFlags {
 //                    const uint8_t* arg_types,
 //                    const uint64_t* arg_values,
 //                    unsigned int flags)
-#define TRACE_EVENT_API_ADD_TRACE_EVENT \
-  node::tracing::TraceEventHelper::GetCurrentPlatform()->AddTraceEvent
+#define TRACE_EVENT_API_ADD_TRACE_EVENT node::tracing::AddTraceEventImpl
 
 // Set the duration field of a COMPLETE trace event.
 // void TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION(
@@ -1252,12 +107,6 @@ enum CategoryGroupEnabledFlags {
 #define TRACE_EVENT_API_ATOMIC_LOAD(var) (var)
 #define TRACE_EVENT_API_ATOMIC_STORE(var, value) (var) = (value)
 
-// The thread buckets for the sampling profiler.
-extern TRACE_EVENT_API_ATOMIC_WORD g_trace_state[3];
-
-#define TRACE_EVENT_API_THREAD_BUCKET(thread_bucket) \
-  g_trace_state[thread_bucket]
-
 ////////////////////////////////////////////////////////////////////////////////
 
 // Implementation detail: trace event macros create temporary variables
@@ -1394,7 +243,7 @@ extern TRACE_EVENT_API_ATOMIC_WORD g_trace_state[3];
     uint64_t cid_;                                                         \
   };                                                                       \
   INTERNAL_TRACE_EVENT_UID(ScopedContext)                                  \
-  INTERNAL_TRACE_EVENT_UID(scoped_context)(context.raw_id());
+  INTERNAL_TRACE_EVENT_UID(scoped_context)(context);
 
 namespace node {
 namespace tracing {
@@ -1405,10 +254,12 @@ const int kZeroNumArgs = 0;
 const decltype(nullptr) kGlobalScope = nullptr;
 const uint64_t kNoId = 0;
 
+extern intptr_t kRuntimeCallStatsTracingEnabled;
+
 class TraceEventHelper {
  public:
-  static void SetCurrentPlatform(v8::Platform* platform);
   static v8::Platform* GetCurrentPlatform();
+  static void SetCurrentPlatform(v8::Platform* platform);
 };
 
 // TraceID encapsulates an ID that can either be an integer or pointer. Pointers
@@ -1540,6 +391,28 @@ class TraceStringWithCopy {
   const char* str_;
 };
 
+static inline uint64_t AddTraceEventImpl(
+    char phase, const uint8_t* category_group_enabled, const char* name,
+    const char* scope, uint64_t id, uint64_t bind_id, int32_t num_args,
+    const char** arg_names, const uint8_t* arg_types,
+    const uint64_t* arg_values, unsigned int flags) {
+  std::unique_ptr<v8::ConvertableToTraceFormat> arg_convertables[2];
+  if (num_args > 0 && arg_types[0] == TRACE_VALUE_TYPE_CONVERTABLE) {
+    arg_convertables[0].reset(reinterpret_cast<v8::ConvertableToTraceFormat*>(
+        static_cast<intptr_t>(arg_values[0])));
+  }
+  if (num_args > 1 && arg_types[1] == TRACE_VALUE_TYPE_CONVERTABLE) {
+    arg_convertables[1].reset(reinterpret_cast<v8::ConvertableToTraceFormat*>(
+        static_cast<intptr_t>(arg_values[1])));
+  }
+  // DCHECK(num_args <= 2);
+  v8::Platform* platform =
+      node::tracing::TraceEventHelper::GetCurrentPlatform();
+  return platform->AddTraceEvent(phase, category_group_enabled, name, scope, id,
+                                 bind_id, num_args, arg_names, arg_types,
+                                 arg_values, arg_convertables, flags);
+}
+
 // Define SetTraceValue for each allowed type. It stores the type and
 // value in the return arguments. This allows this API to avoid declaring any
 // structures so that it is portable to third_party libraries.
@@ -1580,6 +453,19 @@ INTERNAL_DECLARE_SET_TRACE_VALUE(const TraceStringWithCopy&, as_string,
 #undef INTERNAL_DECLARE_SET_TRACE_VALUE
 #undef INTERNAL_DECLARE_SET_TRACE_VALUE_INT
 
+static inline void SetTraceValue(v8::ConvertableToTraceFormat* convertable_value,
+                                    unsigned char* type, uint64_t* value) {
+  *type = TRACE_VALUE_TYPE_CONVERTABLE;
+  *value = static_cast<uint64_t>(reinterpret_cast<intptr_t>(convertable_value));
+}
+
+template <typename T>
+static inline typename std::enable_if<
+    std::is_convertible<T*, v8::ConvertableToTraceFormat*>::value>::type
+SetTraceValue(std::unique_ptr<T> ptr, unsigned char* type, uint64_t* value) {
+  SetTraceValue(ptr.release(), type, value);
+}
+
 // These AddTraceEvent template
 // function is defined here instead of in the macro, because the arg_values
 // could be temporary objects, such as std::string. In order to store
@@ -1592,36 +478,38 @@ static inline uint64_t AddTraceEvent(char phase,
                                         uint64_t id, uint64_t bind_id,
                                         unsigned int flags) {
   return TRACE_EVENT_API_ADD_TRACE_EVENT(phase, category_group_enabled, name,
-                                         scope, id, bind_id, kZeroNumArgs, NULL,
-                                         NULL, NULL, flags);
+                                         scope, id, bind_id, kZeroNumArgs,
+                                         nullptr, nullptr, nullptr, flags);
 }
 
 template <class ARG1_TYPE>
 static inline uint64_t AddTraceEvent(
     char phase, const uint8_t* category_group_enabled, const char* name,
     const char* scope, uint64_t id, uint64_t bind_id, unsigned int flags,
-    const char* arg1_name, const ARG1_TYPE& arg1_val) {
+    const char* arg1_name, ARG1_TYPE&& arg1_val) {
   const int num_args = 1;
-  uint8_t arg_types[1];
-  uint64_t arg_values[1];
-  SetTraceValue(arg1_val, &arg_types[0], &arg_values[0]);
+  uint8_t arg_type;
+  uint64_t arg_value;
+  SetTraceValue(std::forward<ARG1_TYPE>(arg1_val), &arg_type, &arg_value);
   return TRACE_EVENT_API_ADD_TRACE_EVENT(
       phase, category_group_enabled, name, scope, id, bind_id, num_args,
-      &arg1_name, arg_types, arg_values, flags);
+      &arg1_name, &arg_type, &arg_value, flags);
 }
 
 template <class ARG1_TYPE, class ARG2_TYPE>
 static inline uint64_t AddTraceEvent(
     char phase, const uint8_t* category_group_enabled, const char* name,
     const char* scope, uint64_t id, uint64_t bind_id, unsigned int flags,
-    const char* arg1_name, const ARG1_TYPE& arg1_val, const char* arg2_name,
-    const ARG2_TYPE& arg2_val) {
+    const char* arg1_name, ARG1_TYPE&& arg1_val, const char* arg2_name,
+    ARG2_TYPE&& arg2_val) {
   const int num_args = 2;
   const char* arg_names[2] = {arg1_name, arg2_name};
   unsigned char arg_types[2];
   uint64_t arg_values[2];
-  SetTraceValue(arg1_val, &arg_types[0], &arg_values[0]);
-  SetTraceValue(arg2_val, &arg_types[1], &arg_values[1]);
+  SetTraceValue(std::forward<ARG1_TYPE>(arg1_val), &arg_types[0],
+                &arg_values[0]);
+  SetTraceValue(std::forward<ARG2_TYPE>(arg2_val), &arg_types[1],
+                &arg_values[1]);
   return TRACE_EVENT_API_ADD_TRACE_EVENT(
       phase, category_group_enabled, name, scope, id, bind_id, num_args,
       arg_names, arg_types, arg_values, flags);
@@ -1662,48 +550,6 @@ class ScopedTracer {
   Data data_;
 };
 
-// Used by TRACE_EVENT_BINARY_EFFICIENTx macro. Do not use directly.
-class ScopedTraceBinaryEfficient {
- public:
-  ScopedTraceBinaryEfficient(const char* category_group, const char* name);
-  ~ScopedTraceBinaryEfficient();
-
- private:
-  const uint8_t* category_group_enabled_;
-  const char* name_;
-  uint64_t event_handle_;
-};
-
-// TraceEventSamplingStateScope records the current sampling state
-// and sets a new sampling state. When the scope exists, it restores
-// the sampling state having recorded.
-template <size_t BucketNumber>
-class TraceEventSamplingStateScope {
- public:
-  explicit TraceEventSamplingStateScope(const char* category_and_name) {
-    previous_state_ = TraceEventSamplingStateScope<BucketNumber>::Current();
-    TraceEventSamplingStateScope<BucketNumber>::Set(category_and_name);
-  }
-
-  ~TraceEventSamplingStateScope() {
-    TraceEventSamplingStateScope<BucketNumber>::Set(previous_state_);
-  }
-
-  static inline const char* Current() {
-    return reinterpret_cast<const char*>(
-        TRACE_EVENT_API_ATOMIC_LOAD(g_trace_state[BucketNumber]));
-  }
-
-  static inline void Set(const char* category_and_name) {
-    TRACE_EVENT_API_ATOMIC_STORE(g_trace_state[BucketNumber],
-                                 reinterpret_cast<TRACE_EVENT_API_ATOMIC_WORD>(
-                                     const_cast<char*>(category_and_name)));
-  }
-
- private:
-  const char* previous_state_;
-};
-
 }  // namespace tracing
 }  // namespace node
 
diff --git a/src/tracing/trace_event_common.h b/src/tracing/trace_event_common.h
new file mode 100644
index 0000000000..e87665b8cd
--- /dev/null
+++ b/src/tracing/trace_event_common.h
@@ -0,0 +1,1073 @@
+// Copyright 2015 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.
+
+// This header file defines the set of trace_event macros without specifying
+// how the events actually get collected and stored. If you need to expose trace
+// events to some other universe, you can copy-and-paste this file as well as
+// trace_event.h, modifying the macros contained there as necessary for the
+// target platform. The end result is that multiple libraries can funnel events
+// through to a shared trace event collector.
+
+// IMPORTANT: To avoid conflicts, if you need to modify this file for a library,
+// land your change in base/ first, and then copy-and-paste it.
+
+// Trace events are for tracking application performance and resource usage.
+// Macros are provided to track:
+//    Begin and end of function calls
+//    Counters
+//
+// Events are issued against categories. Whereas LOG's
+// categories are statically defined, TRACE categories are created
+// implicitly with a string. For example:
+//   TRACE_EVENT_INSTANT0("MY_SUBSYSTEM", "SomeImportantEvent",
+//                        TRACE_EVENT_SCOPE_THREAD)
+//
+// It is often the case that one trace may belong in multiple categories at the
+// same time. The first argument to the trace can be a comma-separated list of
+// categories, forming a category group, like:
+//
+// TRACE_EVENT_INSTANT0("input,views", "OnMouseOver", TRACE_EVENT_SCOPE_THREAD)
+//
+// We can enable/disable tracing of OnMouseOver by enabling/disabling either
+// category.
+//
+// Events can be INSTANT, or can be pairs of BEGIN and END in the same scope:
+//   TRACE_EVENT_BEGIN0("MY_SUBSYSTEM", "SomethingCostly")
+//   doSomethingCostly()
+//   TRACE_EVENT_END0("MY_SUBSYSTEM", "SomethingCostly")
+// Note: our tools can't always determine the correct BEGIN/END pairs unless
+// these are used in the same scope. Use ASYNC_BEGIN/ASYNC_END macros if you
+// need them to be in separate scopes.
+//
+// A common use case is to trace entire function scopes. This
+// issues a trace BEGIN and END automatically:
+//   void doSomethingCostly() {
+//     TRACE_EVENT0("MY_SUBSYSTEM", "doSomethingCostly");
+//     ...
+//   }
+//
+// Additional parameters can be associated with an event:
+//   void doSomethingCostly2(int howMuch) {
+//     TRACE_EVENT1("MY_SUBSYSTEM", "doSomethingCostly",
+//         "howMuch", howMuch);
+//     ...
+//   }
+//
+// The trace system will automatically add to this information the
+// current process id, thread id, and a timestamp in microseconds.
+//
+// To trace an asynchronous procedure such as an IPC send/receive, use
+// ASYNC_BEGIN and ASYNC_END:
+//   [single threaded sender code]
+//     static int send_count = 0;
+//     ++send_count;
+//     TRACE_EVENT_ASYNC_BEGIN0("ipc", "message", send_count);
+//     Send(new MyMessage(send_count));
+//   [receive code]
+//     void OnMyMessage(send_count) {
+//       TRACE_EVENT_ASYNC_END0("ipc", "message", send_count);
+//     }
+// The third parameter is a unique ID to match ASYNC_BEGIN/ASYNC_END pairs.
+// ASYNC_BEGIN and ASYNC_END can occur on any thread of any traced process.
+// Pointers can be used for the ID parameter, and they will be mangled
+// internally so that the same pointer on two different processes will not
+// match. For example:
+//   class MyTracedClass {
+//    public:
+//     MyTracedClass() {
+//       TRACE_EVENT_ASYNC_BEGIN0("category", "MyTracedClass", this);
+//     }
+//     ~MyTracedClass() {
+//       TRACE_EVENT_ASYNC_END0("category", "MyTracedClass", this);
+//     }
+//   }
+//
+// Trace event also supports counters, which is a way to track a quantity
+// as it varies over time. Counters are created with the following macro:
+//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter", g_myCounterValue);
+//
+// Counters are process-specific. The macro itself can be issued from any
+// thread, however.
+//
+// Sometimes, you want to track two counters at once. You can do this with two
+// counter macros:
+//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter0", g_myCounterValue[0]);
+//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter1", g_myCounterValue[1]);
+// Or you can do it with a combined macro:
+//   TRACE_COUNTER2("MY_SUBSYSTEM", "myCounter",
+//       "bytesPinned", g_myCounterValue[0],
+//       "bytesAllocated", g_myCounterValue[1]);
+// This indicates to the tracing UI that these counters should be displayed
+// in a single graph, as a summed area chart.
+//
+// Since counters are in a global namespace, you may want to disambiguate with a
+// unique ID, by using the TRACE_COUNTER_ID* variations.
+//
+// By default, trace collection is compiled in, but turned off at runtime.
+// Collecting trace data is the responsibility of the embedding
+// application. In Chrome's case, navigating to about:tracing will turn on
+// tracing and display data collected across all active processes.
+//
+//
+// Memory scoping note:
+// Tracing copies the pointers, not the string content, of the strings passed
+// in for category_group, name, and arg_names.  Thus, the following code will
+// cause problems:
+//     char* str = strdup("importantName");
+//     TRACE_EVENT_INSTANT0("SUBSYSTEM", str);  // BAD!
+//     free(str);                   // Trace system now has dangling pointer
+//
+// To avoid this issue with the |name| and |arg_name| parameters, use the
+// TRACE_EVENT_COPY_XXX overloads of the macros at additional runtime overhead.
+// Notes: The category must always be in a long-lived char* (i.e. static const).
+//        The |arg_values|, when used, are always deep copied with the _COPY
+//        macros.
+//
+// When are string argument values copied:
+// const char* arg_values are only referenced by default:
+//     TRACE_EVENT1("category", "name",
+//                  "arg1", "literal string is only referenced");
+// Use TRACE_STR_COPY to force copying of a const char*:
+//     TRACE_EVENT1("category", "name",
+//                  "arg1", TRACE_STR_COPY("string will be copied"));
+// std::string arg_values are always copied:
+//     TRACE_EVENT1("category", "name",
+//                  "arg1", std::string("string will be copied"));
+//
+//
+// Convertable notes:
+// Converting a large data type to a string can be costly. To help with this,
+// the trace framework provides an interface ConvertableToTraceFormat. If you
+// inherit from it and implement the AppendAsTraceFormat method the trace
+// framework will call back to your object to convert a trace output time. This
+// means, if the category for the event is disabled, the conversion will not
+// happen.
+//
+//   class MyData : public base::trace_event::ConvertableToTraceFormat {
+//    public:
+//     MyData() {}
+//     void AppendAsTraceFormat(std::string* out) const override {
+//       out->append("{\"foo\":1}");
+//     }
+//    private:
+//     ~MyData() override {}
+//     DISALLOW_COPY_AND_ASSIGN(MyData);
+//   };
+//
+//   TRACE_EVENT1("foo", "bar", "data",
+//                std::unique_ptr<ConvertableToTraceFormat>(new MyData()));
+//
+// The trace framework will take ownership if the passed pointer and it will
+// be free'd when the trace buffer is flushed.
+//
+// Note, we only do the conversion when the buffer is flushed, so the provided
+// data object should not be modified after it's passed to the trace framework.
+//
+//
+// Thread Safety:
+// A thread safe singleton and mutex are used for thread safety. Category
+// enabled flags are used to limit the performance impact when the system
+// is not enabled.
+//
+// TRACE_EVENT macros first cache a pointer to a category. The categories are
+// statically allocated and safe at all times, even after exit. Fetching a
+// category is protected by the TraceLog::lock_. Multiple threads initializing
+// the static variable is safe, as they will be serialized by the lock and
+// multiple calls will return the same pointer to the category.
+//
+// Then the category_group_enabled flag is checked. This is a unsigned char, and
+// not intended to be multithread safe. It optimizes access to AddTraceEvent
+// which is threadsafe internally via TraceLog::lock_. The enabled flag may
+// cause some threads to incorrectly call or skip calling AddTraceEvent near
+// the time of the system being enabled or disabled. This is acceptable as
+// we tolerate some data loss while the system is being enabled/disabled and
+// because AddTraceEvent is threadsafe internally and checks the enabled state
+// again under lock.
+//
+// Without the use of these static category pointers and enabled flags all
+// trace points would carry a significant performance cost of acquiring a lock
+// and resolving the category.
+
+#if defined(TRACE_EVENT0)
+#error "Another copy of this file has already been included."
+#endif
+
+// This will mark the trace event as disabled by default. The user will need
+// to explicitly enable the event.
+#define TRACE_DISABLED_BY_DEFAULT(name) "disabled-by-default-" name
+
+// Records a pair of begin and end events called "name" for the current
+// scope, with 0, 1 or 2 associated arguments. If the category is not
+// enabled, then this does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_EVENT0(category_group, name)    \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name)
+#define TRACE_EVENT_WITH_FLOW0(category_group, name, bind_id, flow_flags)  \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id, \
+                                            flow_flags)
+#define TRACE_EVENT1(category_group, name, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val)
+#define TRACE_EVENT_WITH_FLOW1(category_group, name, bind_id, flow_flags,  \
+                               arg1_name, arg1_val)                        \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id, \
+                                            flow_flags, arg1_name, arg1_val)
+#define TRACE_EVENT2(category_group, name, arg1_name, arg1_val, arg2_name,   \
+                     arg2_val)                                               \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val, \
+                                  arg2_name, arg2_val)
+#define TRACE_EVENT_WITH_FLOW2(category_group, name, bind_id, flow_flags,    \
+                               arg1_name, arg1_val, arg2_name, arg2_val)     \
+  INTERNAL_TRACE_EVENT_ADD_SCOPED_WITH_FLOW(category_group, name, bind_id,   \
+                                            flow_flags, arg1_name, arg1_val, \
+                                            arg2_name, arg2_val)
+
+// Records a single event called "name" immediately, with 0, 1 or 2
+// associated arguments. If the category is not enabled, then this
+// does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_EVENT_INSTANT0(category_group, name, scope)                   \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE | scope)
+#define TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
+                           TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val)
+#define TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, arg1_val, \
+                             arg2_name, arg2_val)                              \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
+                           TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val, \
+                           arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_INSTANT0(category_group, name, scope)              \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY | scope)
+#define TRACE_EVENT_COPY_INSTANT1(category_group, name, scope, arg1_name,   \
+                                  arg1_val)                                 \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_INSTANT2(category_group, name, scope, arg1_name,      \
+                                  arg1_val, arg2_name, arg2_val)               \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name,    \
+                           TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val, \
+                           arg2_name, arg2_val)
+
+#define TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(category_group, name, scope, \
+                                            timestamp)                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                               \
+      TRACE_EVENT_PHASE_INSTANT, category_group, name, timestamp,        \
+      TRACE_EVENT_FLAG_NONE | scope)
+
+// Records a single BEGIN event called "name" immediately, with 0, 1 or 2
+// associated arguments. If the category is not enabled, then this
+// does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_EVENT_BEGIN0(category_group, name)                          \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_BEGIN1(category_group, name, arg1_name, arg1_val)     \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_BEGIN2(category_group, name, arg1_name, arg1_val,     \
+                           arg2_name, arg2_val)                           \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val,    \
+                           arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_BEGIN0(category_group, name)                     \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_BEGIN1(category_group, name, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name,  \
+                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_BEGIN2(category_group, name, arg1_name, arg1_val, \
+                                arg2_name, arg2_val)                       \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, category_group, name,  \
+                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,     \
+                           arg2_name, arg2_val)
+
+// Similar to TRACE_EVENT_BEGINx but with a custom |at| timestamp provided.
+// - |id| is used to match the _BEGIN event with the _END event.
+//   Events are considered to match if their category_group, name and id values
+//   all match. |id| must either be a pointer or an integer value up to 64 bits.
+//   If it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+#define TRACE_EVENT_BEGIN_WITH_ID_TID_AND_TIMESTAMP0(category_group, name, id, \
+                                                     thread_id, timestamp)     \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id,      \
+      timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP0(                \
+    category_group, name, id, thread_id, timestamp)                       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
+      timestamp, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP1(                \
+    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val)  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
+      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_BEGIN_WITH_ID_TID_AND_TIMESTAMP2(                \
+    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val,  \
+    arg2_name, arg2_val)                                                  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id, thread_id, \
+      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,   \
+      arg2_val)
+
+// Records a single END event for "name" immediately. If the category
+// is not enabled, then this does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_EVENT_END0(category_group, name)                          \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_END1(category_group, name, arg1_name, arg1_val)     \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_END2(category_group, name, arg1_name, arg1_val, arg2_name, \
+                         arg2_val)                                             \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,        \
+                           TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val,         \
+                           arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_END0(category_group, name)                     \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_END1(category_group, name, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,  \
+                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_END2(category_group, name, arg1_name, arg1_val, \
+                              arg2_name, arg2_val)                       \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, category_group, name,  \
+                           TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,   \
+                           arg2_name, arg2_val)
+
+#define TRACE_EVENT_MARK_WITH_TIMESTAMP0(category_group, name, timestamp) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                \
+      TRACE_EVENT_PHASE_MARK, category_group, name, timestamp,            \
+      TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_MARK_WITH_TIMESTAMP1(category_group, name, timestamp, \
+                                         arg1_name, arg1_val)             \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                \
+      TRACE_EVENT_PHASE_MARK, category_group, name, timestamp,            \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+
+#define TRACE_EVENT_COPY_MARK(category_group, name)                      \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_MARK, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY)
+
+#define TRACE_EVENT_COPY_MARK_WITH_TIMESTAMP(category_group, name, timestamp) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                    \
+      TRACE_EVENT_PHASE_MARK, category_group, name, timestamp,                \
+      TRACE_EVENT_FLAG_COPY)
+
+// Similar to TRACE_EVENT_ENDx but with a custom |at| timestamp provided.
+// - |id| is used to match the _BEGIN event with the _END event.
+//   Events are considered to match if their category_group, name and id values
+//   all match. |id| must either be a pointer or an integer value up to 64 bits.
+//   If it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+#define TRACE_EVENT_END_WITH_ID_TID_AND_TIMESTAMP0(category_group, name, id, \
+                                                   thread_id, timestamp)     \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                        \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,      \
+      timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP0(                \
+    category_group, name, id, thread_id, timestamp)                     \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id, \
+      timestamp, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP1(                 \
+    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                    \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,  \
+      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_END_WITH_ID_TID_AND_TIMESTAMP2(                 \
+    category_group, name, id, thread_id, timestamp, arg1_name, arg1_val, \
+    arg2_name, arg2_val)                                                 \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                    \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id, thread_id,  \
+      timestamp, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,  \
+      arg2_val)
+
+// Records the value of a counter called "name" immediately. Value
+// must be representable as a 32 bit integer.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_COUNTER1(category_group, name, value)                         \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE, "value",                  \
+                           static_cast<int>(value))
+#define TRACE_COPY_COUNTER1(category_group, name, value)                    \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY, "value",                  \
+                           static_cast<int>(value))
+
+// Records the values of a multi-parted counter called "name" immediately.
+// The UI will treat value1 and value2 as parts of a whole, displaying their
+// values as a stacked-bar chart.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+#define TRACE_COUNTER2(category_group, name, value1_name, value1_val,       \
+                       value2_name, value2_val)                             \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
+                           TRACE_EVENT_FLAG_NONE, value1_name,              \
+                           static_cast<int>(value1_val), value2_name,       \
+                           static_cast<int>(value2_val))
+#define TRACE_COPY_COUNTER2(category_group, name, value1_name, value1_val,  \
+                            value2_name, value2_val)                        \
+  INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \
+                           TRACE_EVENT_FLAG_COPY, value1_name,              \
+                           static_cast<int>(value1_val), value2_name,       \
+                           static_cast<int>(value2_val))
+
+// Similar to TRACE_COUNTERx, but with a custom |timestamp| provided.
+#define TRACE_COUNTER_WITH_TIMESTAMP1(category_group, name, timestamp, value) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                    \
+      TRACE_EVENT_PHASE_COUNTER, category_group, name, timestamp,             \
+      TRACE_EVENT_FLAG_NONE, "value", static_cast<int>(value))
+
+#define TRACE_COUNTER_WITH_TIMESTAMP2(category_group, name, timestamp,      \
+                                      value1_name, value1_val, value2_name, \
+                                      value2_val)                           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                  \
+      TRACE_EVENT_PHASE_COUNTER, category_group, name, timestamp,           \
+      TRACE_EVENT_FLAG_NONE, value1_name, static_cast<int>(value1_val),     \
+      value2_name, static_cast<int>(value2_val))
+
+// Records the value of a counter called "name" immediately. Value
+// must be representable as a 32 bit integer.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - |id| is used to disambiguate counters with the same name. It must either
+//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
+//   will be xored with a hash of the process ID so that the same pointer on
+//   two different processes will not collide.
+#define TRACE_COUNTER_ID1(category_group, name, id, value)                    \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_NONE, "value",  \
+                                   static_cast<int>(value))
+#define TRACE_COPY_COUNTER_ID1(category_group, name, id, value)               \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_COPY, "value",  \
+                                   static_cast<int>(value))
+
+// Records the values of a multi-parted counter called "name" immediately.
+// The UI will treat value1 and value2 as parts of a whole, displaying their
+// values as a stacked-bar chart.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - |id| is used to disambiguate counters with the same name. It must either
+//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
+//   will be xored with a hash of the process ID so that the same pointer on
+//   two different processes will not collide.
+#define TRACE_COUNTER_ID2(category_group, name, id, value1_name, value1_val,  \
+                          value2_name, value2_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_NONE,           \
+                                   value1_name, static_cast<int>(value1_val), \
+                                   value2_name, static_cast<int>(value2_val))
+#define TRACE_COPY_COUNTER_ID2(category_group, name, id, value1_name,         \
+                               value1_val, value2_name, value2_val)           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_COPY,           \
+                                   value1_name, static_cast<int>(value1_val), \
+                                   value2_name, static_cast<int>(value2_val))
+
+// TRACE_EVENT_SAMPLE_* events are injected by the sampling profiler.
+#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP0(category_group, name,       \
+                                                   thread_id, timestamp)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
+      TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP1(                            \
+    category_group, name, thread_id, timestamp, arg1_name, arg1_val)           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+
+#define TRACE_EVENT_SAMPLE_WITH_TID_AND_TIMESTAMP2(category_group, name,       \
+                                                   thread_id, timestamp,       \
+                                                   arg1_name, arg1_val,        \
+                                                   arg2_name, arg2_val)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_SAMPLE, category_group, name, 0, thread_id, timestamp, \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+
+#define TRACE_EVENT_SAMPLE_WITH_ID1(category_group, name, id, arg1_name,       \
+                                    arg1_val)                                  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_SAMPLE, category_group,   \
+                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
+                                   arg1_val)
+
+// ASYNC_STEP_* APIs should be only used by legacy code. New code should
+// consider using NESTABLE_ASYNC_* APIs to describe substeps within an async
+// event.
+// Records a single ASYNC_BEGIN event called "name" immediately, with 0, 1 or 2
+// associated arguments. If the category is not enabled, then this
+// does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - |id| is used to match the ASYNC_BEGIN event with the ASYNC_END event. ASYNC
+//   events are considered to match if their category_group, name and id values
+//   all match. |id| must either be a pointer or an integer value up to 64 bits.
+//   If it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+//
+// An asynchronous operation can consist of multiple phases. The first phase is
+// defined by the ASYNC_BEGIN calls. Additional phases can be defined using the
+// ASYNC_STEP_INTO or ASYNC_STEP_PAST macros. The ASYNC_STEP_INTO macro will
+// annotate the block following the call. The ASYNC_STEP_PAST macro will
+// annotate the block prior to the call. Note that any particular event must use
+// only STEP_INTO or STEP_PAST macros; they can not mix and match. When the
+// operation completes, call ASYNC_END.
+//
+// An ASYNC trace typically occurs on a single thread (if not, they will only be
+// drawn on the thread defined in the ASYNC_BEGIN event), but all events in that
+// operation must use the same |name| and |id|. Each step can have its own
+// args.
+#define TRACE_EVENT_ASYNC_BEGIN0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
+                                   category_group, name, id,      \
+                                   TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
+                                 arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,     \
+                                   category_group, name, id,          \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
+                                 arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,        \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_ASYNC_BEGIN0(category_group, name, id)   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
+                                   category_group, name, id,      \
+                                   TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
+                                      arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,          \
+                                   category_group, name, id,               \
+                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
+                                      arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                        \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,             \
+      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
+
+// Similar to TRACE_EVENT_ASYNC_BEGINx but with a custom |at| timestamp
+// provided.
+#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, id, \
+                                                timestamp)                \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                     \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,            \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP1(                           \
+    category_group, name, id, timestamp, arg1_name, arg1_val)              \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                      \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,             \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE, \
+      arg1_name, arg1_val)
+#define TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP2(category_group, name, id,      \
+                                                timestamp, arg1_name,          \
+                                                arg1_val, arg2_name, arg2_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,                 \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,     \
+      arg1_name, arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, id, \
+                                                     timestamp)                \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_ASYNC_BEGIN, category_group, name, id,                 \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
+
+// Records a single ASYNC_STEP_INTO event for |step| immediately. If the
+// category is not enabled, then this does nothing. The |name| and |id| must
+// match the ASYNC_BEGIN event above. The |step| param identifies this step
+// within the async event. This should be called at the beginning of the next
+// phase of an asynchronous operation. The ASYNC_BEGIN event must not have any
+// ASYNC_STEP_PAST events.
+#define TRACE_EVENT_ASYNC_STEP_INTO0(category_group, name, id, step)  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP_INTO, \
+                                   category_group, name, id,          \
+                                   TRACE_EVENT_FLAG_NONE, "step", step)
+#define TRACE_EVENT_ASYNC_STEP_INTO1(category_group, name, id, step, \
+                                     arg1_name, arg1_val)            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
+      TRACE_EVENT_PHASE_ASYNC_STEP_INTO, category_group, name, id,   \
+      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
+
+// Similar to TRACE_EVENT_ASYNC_STEP_INTOx but with a custom |at| timestamp
+// provided.
+#define TRACE_EVENT_ASYNC_STEP_INTO_WITH_TIMESTAMP0(category_group, name, id, \
+                                                    step, timestamp)          \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
+      TRACE_EVENT_PHASE_ASYNC_STEP_INTO, category_group, name, id,            \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
+      "step", step)
+
+// Records a single ASYNC_STEP_PAST event for |step| immediately. If the
+// category is not enabled, then this does nothing. The |name| and |id| must
+// match the ASYNC_BEGIN event above. The |step| param identifies this step
+// within the async event. This should be called at the beginning of the next
+// phase of an asynchronous operation. The ASYNC_BEGIN event must not have any
+// ASYNC_STEP_INTO events.
+#define TRACE_EVENT_ASYNC_STEP_PAST0(category_group, name, id, step)  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP_PAST, \
+                                   category_group, name, id,          \
+                                   TRACE_EVENT_FLAG_NONE, "step", step)
+#define TRACE_EVENT_ASYNC_STEP_PAST1(category_group, name, id, step, \
+                                     arg1_name, arg1_val)            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
+      TRACE_EVENT_PHASE_ASYNC_STEP_PAST, category_group, name, id,   \
+      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
+
+// Records a single ASYNC_END event for "name" immediately. If the category
+// is not enabled, then this does nothing.
+#define TRACE_EVENT_ASYNC_END0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
+                                   category_group, name, id,    \
+                                   TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_END1(category_group, name, id, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,               \
+                                   category_group, name, id,                  \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_ASYNC_END2(category_group, name, id, arg1_name, arg1_val, \
+                               arg2_name, arg2_val)                           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                           \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_ASYNC_END0(category_group, name, id)   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
+                                   category_group, name, id,    \
+                                   TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_ASYNC_END1(category_group, name, id, arg1_name, \
+                                    arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,          \
+                                   category_group, name, id,             \
+                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_ASYNC_END2(category_group, name, id, arg1_name, \
+                                    arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                      \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,             \
+      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
+
+// Similar to TRACE_EVENT_ASYNC_ENDx but with a custom |at| timestamp provided.
+#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP0(category_group, name, id, \
+                                              timestamp)                \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,            \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP1(category_group, name, id,       \
+                                              timestamp, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
+      arg1_name, arg1_val)
+#define TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP2(category_group, name, id,       \
+                                              timestamp, arg1_name, arg1_val, \
+                                              arg2_name, arg2_val)            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                         \
+      TRACE_EVENT_PHASE_ASYNC_END, category_group, name, id,                  \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE,    \
+      arg1_name, arg1_val, arg2_name, arg2_val)
+
+// NESTABLE_ASYNC_* APIs are used to describe an async operation, which can
+// be nested within a NESTABLE_ASYNC event and/or have inner NESTABLE_ASYNC
+// events.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - A pair of NESTABLE_ASYNC_BEGIN event and NESTABLE_ASYNC_END event is
+//   considered as a match if their category_group, name and id all match.
+// - |id| must either be a pointer or an integer value up to 64 bits.
+//   If it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+// - |id| is used to match a child NESTABLE_ASYNC event with its parent
+//   NESTABLE_ASYNC event. Therefore, events in the same nested event tree must
+//   be logged using the same id and category_group.
+//
+// Unmatched NESTABLE_ASYNC_END event will be parsed as an event that starts
+// at the first NESTABLE_ASYNC event of that id, and unmatched
+// NESTABLE_ASYNC_BEGIN event will be parsed as an event that ends at the last
+// NESTABLE_ASYNC event of that id. Corresponding warning messages for
+// unmatched events will be shown in the analysis view.
+
+// Records a single NESTABLE_ASYNC_BEGIN event called "name" immediately, with
+// 0, 1 or 2 associated arguments. If the category is not enabled, then this
+// does nothing.
+#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, \
+                                   category_group, name, id,               \
+                                   TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN1(category_group, name, id, arg1_name, \
+                                          arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN,     \
+                                   category_group, name, id,                   \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN2(category_group, name, id, arg1_name, \
+                                          arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+// Records a single NESTABLE_ASYNC_END event called "name" immediately, with 0
+// or 2 associated arguments. If the category is not enabled, then this does
+// nothing.
+#define TRACE_EVENT_NESTABLE_ASYNC_END0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, \
+                                   category_group, name, id,             \
+                                   TRACE_EVENT_FLAG_NONE)
+// Records a single NESTABLE_ASYNC_END event called "name" immediately, with 1
+// associated argument. If the category is not enabled, then this does nothing.
+#define TRACE_EVENT_NESTABLE_ASYNC_END1(category_group, name, id, arg1_name, \
+                                        arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_END,     \
+                                   category_group, name, id,                 \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_NESTABLE_ASYNC_END2(category_group, name, id, arg1_name, \
+                                        arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                          \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,        \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+
+// Records a single NESTABLE_ASYNC_INSTANT event called "name" immediately,
+// with none, one or two associated argument. If the category is not enabled,
+// then this does nothing.
+#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, \
+                                   category_group, name, id,                 \
+                                   TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT1(category_group, name, id,        \
+                                            arg1_name, arg1_val)             \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, \
+                                   category_group, name, id,                 \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+
+#define TRACE_EVENT_NESTABLE_ASYNC_INSTANT2(                              \
+    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT, category_group, name, id, \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+
+#define TRACE_EVENT_COPY_NESTABLE_ASYNC_BEGIN_WITH_TTS2(                       \
+    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
+      TRACE_EVENT_FLAG_ASYNC_TTS | TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
+      arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_NESTABLE_ASYNC_END_WITH_TTS2(                         \
+    category_group, name, id, arg1_name, arg1_val, arg2_name, arg2_val)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,          \
+      TRACE_EVENT_FLAG_ASYNC_TTS | TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
+      arg2_name, arg2_val)
+
+// Similar to TRACE_EVENT_NESTABLE_ASYNC_{BEGIN,END}x but with a custom
+// |timestamp| provided.
+#define TRACE_EVENT_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP0(category_group, name, \
+                                                         id, timestamp)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id,        \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_NESTABLE_ASYNC_END_WITH_TIMESTAMP0(category_group, name, \
+                                                       id, timestamp)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                        \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id,        \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_COPY_NESTABLE_ASYNC_BEGIN_WITH_TIMESTAMP0(          \
+    category_group, name, id, timestamp)                                \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN, category_group, name, id, \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_NESTABLE_ASYNC_END_WITH_TIMESTAMP0(          \
+    category_group, name, id, timestamp)                              \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                 \
+      TRACE_EVENT_PHASE_NESTABLE_ASYNC_END, category_group, name, id, \
+      TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_COPY)
+
+// Records a single FLOW_BEGIN event called "name" immediately, with 0, 1 or 2
+// associated arguments. If the category is not enabled, then this
+// does nothing.
+// - category and name strings must have application lifetime (statics or
+//   literals). They may not include " chars.
+// - |id| is used to match the FLOW_BEGIN event with the FLOW_END event. FLOW
+//   events are considered to match if their category_group, name and id values
+//   all match. |id| must either be a pointer or an integer value up to 64 bits.
+//   If it's a pointer, the bits will be xored with a hash of the process ID so
+//   that the same pointer on two different processes will not collide.
+// FLOW events are different from ASYNC events in how they are drawn by the
+// tracing UI. A FLOW defines asynchronous data flow, such as posting a task
+// (FLOW_BEGIN) and later executing that task (FLOW_END). Expect FLOWs to be
+// drawn as lines or arrows from FLOW_BEGIN scopes to FLOW_END scopes. Similar
+// to ASYNC, a FLOW can consist of multiple phases. The first phase is defined
+// by the FLOW_BEGIN calls. Additional phases can be defined using the FLOW_STEP
+// macros. When the operation completes, call FLOW_END. An async operation can
+// span threads and processes, but all events in that operation must use the
+// same |name| and |id|. Each event can have its own args.
+#define TRACE_EVENT_FLOW_BEGIN0(category_group, name, id)        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
+                                   category_group, name, id,     \
+                                   TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_FLOW_BEGIN1(category_group, name, id, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,               \
+                                   category_group, name, id,                   \
+                                   TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
+#define TRACE_EVENT_FLOW_BEGIN2(category_group, name, id, arg1_name, arg1_val, \
+                                arg2_name, arg2_val)                           \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
+      TRACE_EVENT_PHASE_FLOW_BEGIN, category_group, name, id,                  \
+      TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_FLOW_BEGIN0(category_group, name, id)   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
+                                   category_group, name, id,     \
+                                   TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_FLOW_BEGIN1(category_group, name, id, arg1_name, \
+                                     arg1_val)                            \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,          \
+                                   category_group, name, id,              \
+                                   TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_FLOW_BEGIN2(category_group, name, id, arg1_name, \
+                                     arg1_val, arg2_name, arg2_val)       \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
+      TRACE_EVENT_PHASE_FLOW_BEGIN, category_group, name, id,             \
+      TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
+
+// Records a single FLOW_STEP event for |step| immediately. If the category
+// is not enabled, then this does nothing. The |name| and |id| must match the
+// FLOW_BEGIN event above. The |step| param identifies this step within the
+// async event. This should be called at the beginning of the next phase of an
+// asynchronous operation.
+#define TRACE_EVENT_FLOW_STEP0(category_group, name, id, step)  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
+                                   category_group, name, id,    \
+                                   TRACE_EVENT_FLAG_NONE, "step", step)
+#define TRACE_EVENT_FLOW_STEP1(category_group, name, id, step, arg1_name, \
+                               arg1_val)                                  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                       \
+      TRACE_EVENT_PHASE_FLOW_STEP, category_group, name, id,              \
+      TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
+#define TRACE_EVENT_COPY_FLOW_STEP0(category_group, name, id, step) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP,     \
+                                   category_group, name, id,        \
+                                   TRACE_EVENT_FLAG_COPY, "step", step)
+#define TRACE_EVENT_COPY_FLOW_STEP1(category_group, name, id, step, arg1_name, \
+                                    arg1_val)                                  \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                            \
+      TRACE_EVENT_PHASE_FLOW_STEP, category_group, name, id,                   \
+      TRACE_EVENT_FLAG_COPY, "step", step, arg1_name, arg1_val)
+
+// Records a single FLOW_END event for "name" immediately. If the category
+// is not enabled, then this does nothing.
+#define TRACE_EVENT_FLOW_END0(category_group, name, id)                        \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_FLOW_END_BIND_TO_ENCLOSING0(category_group, name, id)      \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id,                                   \
+                                   TRACE_EVENT_FLAG_BIND_TO_ENCLOSING)
+#define TRACE_EVENT_FLOW_END1(category_group, name, id, arg1_name, arg1_val)   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
+                                   arg1_val)
+#define TRACE_EVENT_FLOW_END2(category_group, name, id, arg1_name, arg1_val,   \
+                              arg2_name, arg2_val)                             \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_NONE, arg1_name, \
+                                   arg1_val, arg2_name, arg2_val)
+#define TRACE_EVENT_COPY_FLOW_END0(category_group, name, id)                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_COPY)
+#define TRACE_EVENT_COPY_FLOW_END1(category_group, name, id, arg1_name,        \
+                                   arg1_val)                                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
+                                   arg1_val)
+#define TRACE_EVENT_COPY_FLOW_END2(category_group, name, id, arg1_name,        \
+                                   arg1_val, arg2_name, arg2_val)              \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, category_group, \
+                                   name, id, TRACE_EVENT_FLAG_COPY, arg1_name, \
+                                   arg1_val, arg2_name, arg2_val)
+
+// Special trace event macro to trace task execution with the location where it
+// was posted from.
+#define TRACE_TASK_EXECUTION(run_function, task) \
+  INTERNAL_TRACE_TASK_EXECUTION(run_function, task)
+
+// TRACE_EVENT_METADATA* events are information related to other
+// injected events, not events in their own right.
+#define TRACE_EVENT_METADATA1(category_group, name, arg1_name, arg1_val) \
+  INTERNAL_TRACE_EVENT_METADATA_ADD(category_group, name, arg1_name, arg1_val)
+
+// Records a clock sync event.
+#define TRACE_EVENT_CLOCK_SYNC_RECEIVER(sync_id)                               \
+  INTERNAL_TRACE_EVENT_ADD(                                                    \
+      TRACE_EVENT_PHASE_CLOCK_SYNC, "__metadata", "clock_sync",                \
+      TRACE_EVENT_FLAG_NONE, "sync_id", sync_id)
+#define TRACE_EVENT_CLOCK_SYNC_ISSUER(sync_id, issue_ts, issue_end_ts)         \
+  INTERNAL_TRACE_EVENT_ADD_WITH_TIMESTAMP(                                     \
+      TRACE_EVENT_PHASE_CLOCK_SYNC, "__metadata", "clock_sync",                \
+      issue_end_ts, TRACE_EVENT_FLAG_NONE,                                     \
+      "sync_id", sync_id, "issue_ts", issue_ts)
+
+// Macros to track the life time and value of arbitrary client objects.
+// See also TraceTrackableObject.
+#define TRACE_EVENT_OBJECT_CREATED_WITH_ID(category_group, name, id) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
+      TRACE_EVENT_PHASE_CREATE_OBJECT, category_group, name, id,     \
+      TRACE_EVENT_FLAG_NONE)
+
+#define TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID(category_group, name, id, \
+                                            snapshot)                 \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
+      TRACE_EVENT_PHASE_SNAPSHOT_OBJECT, category_group, name,        \
+      id, TRACE_EVENT_FLAG_NONE, "snapshot", snapshot)
+
+#define TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID_AND_TIMESTAMP(                     \
+    category_group, name, id, timestamp, snapshot)                             \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                          \
+      TRACE_EVENT_PHASE_SNAPSHOT_OBJECT, category_group, name,                 \
+      id, TRACE_EVENT_API_CURRENT_THREAD_ID, timestamp, TRACE_EVENT_FLAG_NONE, \
+      "snapshot", snapshot)
+
+#define TRACE_EVENT_OBJECT_DELETED_WITH_ID(category_group, name, id) \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                  \
+      TRACE_EVENT_PHASE_DELETE_OBJECT, category_group, name, id,     \
+      TRACE_EVENT_FLAG_NONE)
+
+// Records entering and leaving trace event contexts. |category_group| and
+// |name| specify the context category and type. |context| is a
+// snapshotted context object id.
+#define TRACE_EVENT_ENTER_CONTEXT(category_group, name, context)      \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
+      TRACE_EVENT_PHASE_ENTER_CONTEXT, category_group, name, context, \
+      TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_LEAVE_CONTEXT(category_group, name, context)      \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                   \
+      TRACE_EVENT_PHASE_LEAVE_CONTEXT, category_group, name, context, \
+      TRACE_EVENT_FLAG_NONE)
+#define TRACE_EVENT_SCOPED_CONTEXT(category_group, name, context) \
+  INTERNAL_TRACE_EVENT_SCOPED_CONTEXT(category_group, name, context)
+
+// Macro to specify that two trace IDs are identical. For example,
+// TRACE_LINK_IDS(
+//     "category", "name",
+//     TRACE_ID_WITH_SCOPE("net::URLRequest", 0x1000),
+//     TRACE_ID_WITH_SCOPE("blink::ResourceFetcher::FetchRequest", 0x2000))
+// tells the trace consumer that events with ID ("net::URLRequest", 0x1000) from
+// the current process have the same ID as events with ID
+// ("blink::ResourceFetcher::FetchRequest", 0x2000).
+#define TRACE_LINK_IDS(category_group, name, id, linked_id) \
+  INTERNAL_TRACE_EVENT_ADD_LINK_IDS(category_group, name, id, linked_id);
+
+// Macro to efficiently determine if a given category group is enabled.
+#define TRACE_EVENT_CATEGORY_GROUP_ENABLED(category_group, ret)             \
+  do {                                                                      \
+    INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group);                 \
+    if (INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE()) { \
+      *ret = true;                                                          \
+    } else {                                                                \
+      *ret = false;                                                         \
+    }                                                                       \
+  } while (0)
+
+// Macro to explicitly warm up a given category group. This could be useful in
+// cases where we want to initialize a category group before any trace events
+// for that category group is reported. For example, to have a category group
+// always show up in the "record categories" list for manually selecting
+// settings in about://tracing.
+#define TRACE_EVENT_WARMUP_CATEGORY(category_group) \
+  INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group)
+
+// Macro to efficiently determine, through polling, if a new trace has begun.
+#define TRACE_EVENT_IS_NEW_TRACE(ret)                                      \
+  do {                                                                     \
+    static int INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = 0;          \
+    int num_traces_recorded = TRACE_EVENT_API_GET_NUM_TRACES_RECORDED();   \
+    if (num_traces_recorded != -1 &&                                       \
+        num_traces_recorded !=                                             \
+            INTERNAL_TRACE_EVENT_UID(lastRecordingNumber)) {               \
+      INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = num_traces_recorded; \
+      *ret = true;                                                         \
+    } else {                                                               \
+      *ret = false;                                                        \
+    }                                                                      \
+  } while (0)
+
+// Notes regarding the following definitions:
+// New values can be added and propagated to third party libraries, but existing
+// definitions must never be changed, because third party libraries may use old
+// definitions.
+
+// Phase indicates the nature of an event entry. E.g. part of a begin/end pair.
+#define TRACE_EVENT_PHASE_BEGIN ('B')
+#define TRACE_EVENT_PHASE_END ('E')
+#define TRACE_EVENT_PHASE_COMPLETE ('X')
+#define TRACE_EVENT_PHASE_INSTANT ('I')
+#define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S')
+#define TRACE_EVENT_PHASE_ASYNC_STEP_INTO ('T')
+#define TRACE_EVENT_PHASE_ASYNC_STEP_PAST ('p')
+#define TRACE_EVENT_PHASE_ASYNC_END ('F')
+#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN ('b')
+#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_END ('e')
+#define TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT ('n')
+#define TRACE_EVENT_PHASE_FLOW_BEGIN ('s')
+#define TRACE_EVENT_PHASE_FLOW_STEP ('t')
+#define TRACE_EVENT_PHASE_FLOW_END ('f')
+#define TRACE_EVENT_PHASE_METADATA ('M')
+#define TRACE_EVENT_PHASE_COUNTER ('C')
+#define TRACE_EVENT_PHASE_SAMPLE ('P')
+#define TRACE_EVENT_PHASE_CREATE_OBJECT ('N')
+#define TRACE_EVENT_PHASE_SNAPSHOT_OBJECT ('O')
+#define TRACE_EVENT_PHASE_DELETE_OBJECT ('D')
+#define TRACE_EVENT_PHASE_MEMORY_DUMP ('v')
+#define TRACE_EVENT_PHASE_MARK ('R')
+#define TRACE_EVENT_PHASE_CLOCK_SYNC ('c')
+#define TRACE_EVENT_PHASE_ENTER_CONTEXT ('(')
+#define TRACE_EVENT_PHASE_LEAVE_CONTEXT (')')
+#define TRACE_EVENT_PHASE_LINK_IDS ('=')
+
+// Flags for changing the behavior of TRACE_EVENT_API_ADD_TRACE_EVENT.
+#define TRACE_EVENT_FLAG_NONE (static_cast<unsigned int>(0))
+#define TRACE_EVENT_FLAG_COPY (static_cast<unsigned int>(1 << 0))
+#define TRACE_EVENT_FLAG_HAS_ID (static_cast<unsigned int>(1 << 1))
+// TODO(crbug.com/639003): Free this bit after ID mangling is deprecated.
+#define TRACE_EVENT_FLAG_MANGLE_ID (static_cast<unsigned int>(1 << 2))
+#define TRACE_EVENT_FLAG_SCOPE_OFFSET (static_cast<unsigned int>(1 << 3))
+#define TRACE_EVENT_FLAG_SCOPE_EXTRA (static_cast<unsigned int>(1 << 4))
+#define TRACE_EVENT_FLAG_EXPLICIT_TIMESTAMP (static_cast<unsigned int>(1 << 5))
+#define TRACE_EVENT_FLAG_ASYNC_TTS (static_cast<unsigned int>(1 << 6))
+#define TRACE_EVENT_FLAG_BIND_TO_ENCLOSING (static_cast<unsigned int>(1 << 7))
+#define TRACE_EVENT_FLAG_FLOW_IN (static_cast<unsigned int>(1 << 8))
+#define TRACE_EVENT_FLAG_FLOW_OUT (static_cast<unsigned int>(1 << 9))
+#define TRACE_EVENT_FLAG_HAS_CONTEXT_ID (static_cast<unsigned int>(1 << 10))
+#define TRACE_EVENT_FLAG_HAS_PROCESS_ID (static_cast<unsigned int>(1 << 11))
+#define TRACE_EVENT_FLAG_HAS_LOCAL_ID (static_cast<unsigned int>(1 << 12))
+#define TRACE_EVENT_FLAG_HAS_GLOBAL_ID (static_cast<unsigned int>(1 << 13))
+
+#define TRACE_EVENT_FLAG_SCOPE_MASK                          \
+  (static_cast<unsigned int>(TRACE_EVENT_FLAG_SCOPE_OFFSET | \
+                             TRACE_EVENT_FLAG_SCOPE_EXTRA))
+
+// Type values for identifying types in the TraceValue union.
+#define TRACE_VALUE_TYPE_BOOL (static_cast<unsigned char>(1))
+#define TRACE_VALUE_TYPE_UINT (static_cast<unsigned char>(2))
+#define TRACE_VALUE_TYPE_INT (static_cast<unsigned char>(3))
+#define TRACE_VALUE_TYPE_DOUBLE (static_cast<unsigned char>(4))
+#define TRACE_VALUE_TYPE_POINTER (static_cast<unsigned char>(5))
+#define TRACE_VALUE_TYPE_STRING (static_cast<unsigned char>(6))
+#define TRACE_VALUE_TYPE_COPY_STRING (static_cast<unsigned char>(7))
+#define TRACE_VALUE_TYPE_CONVERTABLE (static_cast<unsigned char>(8))
+
+// Enum reflecting the scope of an INSTANT event. Must fit within
+// TRACE_EVENT_FLAG_SCOPE_MASK.
+#define TRACE_EVENT_SCOPE_GLOBAL (static_cast<unsigned char>(0 << 3))
+#define TRACE_EVENT_SCOPE_PROCESS (static_cast<unsigned char>(1 << 3))
+#define TRACE_EVENT_SCOPE_THREAD (static_cast<unsigned char>(2 << 3))
+
+#define TRACE_EVENT_SCOPE_NAME_GLOBAL ('g')
+#define TRACE_EVENT_SCOPE_NAME_PROCESS ('p')
+#define TRACE_EVENT_SCOPE_NAME_THREAD ('t')