[webkit-changes] [WebKit/WebKit] 3fabfe: REGRESSION (261253 at main): Editing GitHub comment q...

[Alan Baradlay]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 3fabfea068b81f41e1c30cde8743a744aaa12dc9
      https://github.com/WebKit/WebKit/commit/3fabfea068b81f41e1c30cde8743a744aaa12dc9
  Author: Alan Baradlay <zalan at apple.com>
  Date:   2023-03-16 (Thu, 16 Mar 2023)

  Changed paths:
    M Source/WebCore/Sources.txt
    M Source/WebCore/WebCore.xcodeproj/project.pbxproj
    A Source/WebCore/layout/formattingContexts/inline/display/InlineDisplayContent.cpp
    M Source/WebCore/layout/formattingContexts/inline/display/InlineDisplayContent.h
    M Source/WebCore/layout/formattingContexts/inline/invalidation/InlineInvalidation.h

  Log Message:
  -----------
  REGRESSION (261253 at main): Editing GitHub comment quickly can cause flickering text/switching spellcheck suggestions and empty spaces
https://bugs.webkit.org/show_bug.cgi?id=253985
<rdar://106708219>

Reviewed by Simon Fraser.

Let's invalidate the glyph cache whenever we destroy an associated display box. This is similar to what legacy line layout does by calling removeGlyphDisplayList from ~LegacyInlineTextBox.

1. GlyphDisplayListCache uses display box's address as key.
2. When we destroy/create display boxes through partial layout, entries in GlyphDisplayListCache become stale...however if a newly constructed display box happens
to land on the same address, we end up reusing a stale entry and paint "old" content.
3. With no partial layout enabled GlyphDisplayListCache was cleared right before each and every layout.

* Source/WebCore/Sources.txt:
* Source/WebCore/WebCore.xcodeproj/project.pbxproj:
* Source/WebCore/layout/formattingContexts/inline/display/InlineDisplayContent.cpp: Copied from Source/WebCore/layout/formattingContexts/inline/display/InlineDisplayContent.h.
(WebCore::InlineDisplay::invalidateGlyphCache):
(WebCore::InlineDisplay::Content::clear):
(WebCore::InlineDisplay::Content::set):
(WebCore::InlineDisplay::Content::append):
(WebCore::InlineDisplay::Content::remove):
* Source/WebCore/layout/formattingContexts/inline/display/InlineDisplayContent.h:
(WebCore::InlineDisplay::Content::clear): Deleted.
(WebCore::InlineDisplay::Content::set): Deleted.
(WebCore::InlineDisplay::Content::append): Deleted.
(WebCore::InlineDisplay::Content::remove): Deleted.

Canonical link: https://commits.webkit.org/261743@main