doc: addresses nits in string_decoder, url, util

- Only `@@toStringTag` affects `util.isError()`, this is the reason why
it uses `Object.prototype.toString.call(argument)` under the hood.
- Shows an actual Euro symbol for reference.
- Uses line-drawing characters for the URL chart & fixes the chart
borders.

PR-URL: https://github.com/nodejs/node/pull/7026
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/doc/api/string_decoder.md b/doc/api/string_decoder.md
index 43ea739f4b..6bd5a57502 100644
--- a/doc/api/string_decoder.md
+++ b/doc/api/string_decoder.md
@@ -28,8 +28,8 @@ internal buffer is used to ensure that the decoded string does not contain
 any incomplete multibyte characters. These are held in the buffer until the
 next call to `stringDecoder.write()` or until `stringDecoder.end()` is called.
 
-In the following example, the three UTF-8 encoded bytes of the European euro
-symbol are written over three separate operations:
+In the following example, the three UTF-8 encoded bytes of the European Euro
+symbol (`€`) are written over three separate operations:
 
 ```js
 const StringDecoder = require('string_decoder').StringDecoder;