[webkit-changes] [WebKit/WebKit] b2c286: Remove the isLoadingCustomFonts() check in FontCa...

[Simon Fraser]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: b2c286c1a7c173f053bbca6fb2d53e1d5806e0a1
      https://github.com/WebKit/WebKit/commit/b2c286c1a7c173f053bbca6fb2d53e1d5806e0a1
  Author: Simon Fraser <simon.fraser at apple.com>
  Date:   2024-01-04 (Thu, 04 Jan 2024)

  Changed paths:
    M Source/WebCore/platform/graphics/FontCascade.cpp

  Log Message:
  -----------
  Remove the isLoadingCustomFonts() check in  FontCascade::operator==
https://bugs.webkit.org/show_bug.cgi?id=267083
<rdar://problem/120478069>

Reviewed by Cameron McCormack.

The first landing of custom font support (20474 at main) made it so that any FontCascade
comparison would return false if either side was loading custom fonts. But this makes
it impossible to use pointer equality in RenderStyle::diff() code, and could trigger
lots of extra layouts and painting while custom fonts are loading.

FontCascade::operator== already checks both `generation()` and `fontSelectorVersion()`
which increment as fonts load, so remove the isLoadingCustomFonts() check.

* Source/WebCore/platform/graphics/FontCascade.cpp:
(WebCore::FontCascade::operator== const):

Canonical link: https://commits.webkit.org/272673@main