[webkit-changes] [WebKit/WebKit] 5326da: Inline style should always be cacheable in matched...

[Antti Koivisto]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 5326da20993d8ae1af4adfcf9efecbed999adec0
      https://github.com/WebKit/WebKit/commit/5326da20993d8ae1af4adfcf9efecbed999adec0
  Author: Antti Koivisto <antti at apple.com>
  Date:   2023-08-18 (Fri, 18 Aug 2023)

  Changed paths:
    M Source/WebCore/dom/ElementData.cpp
    M Source/WebCore/dom/ElementData.h
    M Source/WebCore/dom/StyledElement.cpp
    M Source/WebCore/dom/StyledElement.h
    M Source/WebCore/style/ElementRuleCollector.cpp

  Log Message:
  -----------
  Inline style should always be cacheable in matched declarations cache
https://bugs.webkit.org/show_bug.cgi?id=260254
rdar://113960228

Reviewed by Alan Baradlay.

Mutable inline style (created by modification via JS wrapper) prevents style caching
in the matched declarations cache. This patch turns any mutable style immutable during
style resolution so we can cache it. Due to deduplication the cache entries can be reused
accross elements and mutations.

* Source/WebCore/dom/ElementData.cpp:
(WebCore::UniqueElementData::UniqueElementData):
* Source/WebCore/dom/ElementData.h:

Save the immutable style in UniqueElementData.

* Source/WebCore/dom/StyledElement.cpp:
(WebCore::StyledElement::styleAttributeChanged):
(WebCore::StyledElement::invalidateStyleAttribute):

Take care to invalidate the cached immutable copy.

(WebCore::StyledElement::inlineStyleForStyleResolution const):

The accessor constructs ImmutableStyleProperties lazily on demand.

* Source/WebCore/dom/StyledElement.h:
* Source/WebCore/style/ElementRuleCollector.cpp:
(WebCore::Style::ElementRuleCollector::addElementInlineStyleProperties):

Allow caching.

Canonical link: https://commits.webkit.org/267035@main