[UI-side compositing] Ensure that wheel events got to the web process for JS event handlers

[smfr]

066e5bd

[UI-side compositing] Ensure that wheel events got to the web process for JS event handlers
https://bugs.webkit.org/show_bug.cgi?id=248846

Reviewed by Tim Horton.

Override `eventListenerRegionTypesForPoint()` in RemoteScrollingTreeMac just as we do in ScrollingTreeMac
to get the event handler details for a given point. We use this to know if we have to continue with the
web process/main thread event handling path.

* Source/WebKit/UIProcess/RemoteLayerTree/mac/RemoteScrollingTreeMac.h:
* Source/WebKit/UIProcess/RemoteLayerTree/mac/RemoteScrollingTreeMac.mm:
(WebKit::eventRegionForLayer):
(WebKit::layerEventRegionContainsPoint):
(WebKit::RemoteScrollingTreeMac::eventListenerRegionTypesForPoint const):

Canonical link: https://commits.webkit.org/257531@main

1df06c2

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

[webkit-early-warning-system]

EWS run on current version of this PR (hash 1df06c2)

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

[webkit-commit-queue]

Committed 257531@main (066e5bd): https://commits.webkit.org/257531@main

Reviewed commits have been landed. Closing PR #7234 and removing active labels.