Remove ShadowRoot::resetStyleInheritance mechanism

[anttijk]

121c1a4

Remove ShadowRoot::resetStyleInheritance mechanism
https://bugs.webkit.org/show_bug.cgi?id=260338
rdar://114015755

Reviewed by Alan Baradlay.

UA shadow trees should just use 'all: initial' if needed.

* Source/WebCore/dom/ShadowRoot.cpp:
(WebCore::ShadowRoot::setResetStyleInheritance): Deleted.
* Source/WebCore/dom/ShadowRoot.h:
* Source/WebCore/html/HTMLPlugInElement.cpp:
(WebCore::HTMLPlugInElement::didAddUserAgentShadowRoot):
* Source/WebCore/html/shadow/ShadowPseudoIds.cpp:
(WebCore::ShadowPseudoIds::webkitPluginReplacement): Deleted.

Also remove this non-referenced pseudo element name.

* Source/WebCore/html/shadow/ShadowPseudoIds.h:
* Source/WebCore/html/shadow/YouTubeEmbedShadowElement.cpp:

This is the only client for the mechanism, use 'all:initial' instead.

(WebCore::YouTubeEmbedShadowElement::create):
* Source/WebCore/style/StyleResolver.cpp:
(WebCore::Style::Resolver::State::State):

Canonical link: https://commits.webkit.org/266999@main

62c995f

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 62c995f)

Details

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🛠 gtk
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2
	✅ 🛠 tv-sim
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 266999@main (121c1a4): https://commits.webkit.org/266999@main

Reviewed commits have been landed. Closing PR #16781 and removing active labels.