[webkit-changes] [WebKit/WebKit] 023c54: Support all of HTML's character entities in WebVTT

[Kohei Ueno]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 023c54054092dc68c5df3b230ed3137cbd753b16
      https://github.com/WebKit/WebKit/commit/023c54054092dc68c5df3b230ed3137cbd753b16
  Author: Kohei Ueno <kohei.ueno119 at gmail.com>
  Date:   2023-11-04 (Sat, 04 Nov 2023)

  Changed paths:
    M LayoutTests/imported/w3c/web-platform-tests/webvtt/parsing/cue-text-parsing/tests/entities-expected.txt
    M Source/WebCore/html/track/WebVTTTokenizer.cpp

  Log Message:
  -----------
  Support all of HTML's character entities in WebVTT
https://bugs.webkit.org/show_bug.cgi?id=176225

Reviewed by Darin Adler.

WebVTT cue text tokenizer algorithm has been updated to support
all of HTML's character entities in https://github.com/w3c/webvtt/pull/253.
This patch updates the tokenizer to align with the latest spec.
Spec: https://w3c.github.io/webvtt/#webvtt-cue-text-tokenizer

The old `EscapeState` state for handling escape characters has been
removed in favor of new two states. And the `WEBVTT_SWITCH_TO` operation
has been added for the purpose of enabling state transition without
the requirement to advance the input position.

* LayoutTests/imported/w3c/web-platform-tests/webvtt/parsing/cue-text-parsing/tests/entities-expected.txt:
* Source/WebCore/html/track/WebVTTTokenizer.cpp:
(WebCore::ProcessEntity):
(WebCore::WebVTTTokenizer::nextToken):

Canonical link: https://commits.webkit.org/270240@main