Implement the active custom element constructor map

[annevk]

48915d8

Implement the active custom element constructor map
https://bugs.webkit.org/show_bug.cgi?id=319658

Reviewed by Ryosuke Niwa.

Keith Cirkel pointed out that the constructor map as defined did not
quite work and also that WebKit did not implement it.

This aligns WebKit with the proposed changes to DOM and HTML and also
adds some additional test coverage for the gaps:

- whatwg/dom#1494
- whatwg/html#12696

Tests: imported/w3c/web-platform-tests/custom-elements/createElement-reentrant-construction.window.html
       imported/w3c/web-platform-tests/custom-elements/registries/constructor-direct-call-fallback-registry.window.html
       imported/w3c/web-platform-tests/custom-elements/registries/constructor-reentry-createElement.window.html

Canonical link: https://commits.webkit.org/317462@main

72ac26b

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows	Apple Internal
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	⏳ 🛠 win	✅ 🛠 ios-apple
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	⏳ 🧪 win-tests	🛠 mac-apple
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe		✅ 🛠 vision-apple
	✅ 🧪 ios-wk2-wpt	✅ 🧪 api-mac-debug	✅ 🛠 gtk3-libwebrtc
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 ios-safer-cpp	🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 vision-sim	🧪 mac-intel-wk2	✅ 🛠 playstation
✅ 🛠 🧪 unsafe-merge	✅ 🧪 vision-wk2	✅ 🛠 mac-safer-cpp
	✅ 🛠 tv	❌ 🧪 mac-site-isolation
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 1e861ff)

Details

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows	Apple Internal
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	🛠 win	⏳ 🛠 ios-apple
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	🧪 win-tests	⏳ 🛠 mac-apple
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe		⏳ 🛠 vision-apple
	✅ 🧪 ios-wk2-wpt	✅ 🧪 api-mac-debug	✅ 🛠 gtk3-libwebrtc
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 ios-safer-cpp	✅ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 vision	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 vision-sim	✅ 🧪 mac-intel-wk2	✅ 🛠 playstation
	✅ 🧪 vision-wk2	✅ 🛠 mac-safer-cpp
	✅ 🛠 tv	✅ 🧪 mac-site-isolation
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 72ac26b)

Details

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows	Apple Internal
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	⏳ 🛠 win	✅ 🛠 ios-apple
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	⏳ 🧪 win-tests	🛠 mac-apple
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe		✅ 🛠 vision-apple
	✅ 🧪 ios-wk2-wpt	✅ 🧪 api-mac-debug	✅ 🛠 gtk3-libwebrtc
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 ios-safer-cpp	🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 vision-sim	🧪 mac-intel-wk2	✅ 🛠 playstation
✅ 🛠 🧪 unsafe-merge	✅ 🧪 vision-wk2	✅ 🛠 mac-safer-cpp
	✅ 🛠 tv	❌ 🧪 mac-site-isolation
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 317462@main (48915d8): https://commits.webkit.org/317462@main

Reviewed commits have been landed. Closing PR #69639 and removing active labels.