CSS Custom Highlights text decoration does not respect priority

[jesxilin]

bf94cf5

CSS Custom Highlights text decoration does not respect priority
https://bugs.webkit.org/show_bug.cgi?id=259321
rdar://112494779

Reviewed by Wenson Hsieh.

Before if StyledMarkedText was of higher priority, just overrides textDecorationStyles.
Added a function to compute the textDecorationStyles.
Added WPT ref test for painting unclashing lower priority text decoration
over higher priority highlight without text decorations.

* LayoutTests/imported/w3c/web-platform-tests/css/css-highlight-api/painting/custom-highlight-painting-priority-text-decoration-001-expected.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/css/css-highlight-api/painting/custom-highlight-painting-priority-text-decoration-001-ref.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/css/css-highlight-api/painting/custom-highlight-painting-priority-text-decoration-001.html: Added.
* Source/WebCore/rendering/StyledMarkedText.cpp:
(WebCore::computeStylesForTextDecorations):
(WebCore::coalesceAdjacentWithSameRanges):

Canonical link: https://commits.webkit.org/266184@main

2bee93c

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	✅ 🧪 mac-wk2-stress
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash e52fbf4)

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
	✅ 🛠 watch
	✅ 🛠 watch-sim

[pxlcoder]

Can we add a test?

[webkit-early-warning-system]

EWS run on current version of this PR (hash 2bee93c)

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	✅ 🧪 mac-wk2-stress
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 266184@main (bf94cf5): https://commits.webkit.org/266184@main

Reviewed commits have been landed. Closing PR #15919 and removing active labels.