Add tracepoints around WebXR frame rendering

[achan00]

8025107

Add tracepoints around WebXR frame rendering
https://bugs.webkit.org/show_bug.cgi?id=271474
rdar://125215811

Reviewed by Kimmo Kinnunen.

* Source/WTF/wtf/SystemTracing.h:
* Source/WebCore/Modules/webxr/WebXROpaqueFramebuffer.cpp:
(WebCore::WebXROpaqueFramebuffer::startFrame):
(WebCore::WebXROpaqueFramebuffer::endFrame):
* Source/WebCore/Modules/webxr/WebXRSession.cpp:
(WebCore::WebXRSession::onFrame):
* Source/WebKit/Resources/Signposts/SystemTracePoints.plist:

Canonical link: https://commits.webkit.org/276571@main

9f34acf

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	✅ 🧪 api-wpe
	🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-skia
🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	🛠 tv	✅ 🧪 mac-AS-debug-wk2	⏳ 🧪 gtk-wk2
	✅ 🛠 tv-sim		⏳ 🧪 api-gtk
✅ 🛠 🧪 merge	🛠 watch		✅ 🛠 jsc-armv7
	✅ 🛠 watch-sim		🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash e924ab3)

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	🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-skia
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 tv-sim		✅ 🧪 api-gtk
	🛠 watch		✅ 🛠 jsc-armv7
	✅ 🛠 watch-sim		⏳ 🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 7881895)

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	✅ 🧪 api-wpe
	⏳ 🧪 ios-wk2-wpt	🧪 mac-wk1	✅ 🛠 wpe-skia
🛠 🧪 jsc	⏳ 🧪 api-ios	🧪 mac-wk2	✅ 🛠 gtk
🛠 🧪 jsc-arm64	🛠 tv	⏳ 🧪 mac-AS-debug-wk2	⏳ 🧪 gtk-wk2
	🛠 tv-sim		⏳ 🧪 api-gtk
	🛠 watch		✅ 🛠 jsc-armv7
	✅ 🛠 watch-sim		⏳ 🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 1f625d6)

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	🧪 api-wpe
	⏳ 🧪 ios-wk2-wpt	🧪 mac-wk1	✅ 🛠 wpe-skia
🛠 🧪 jsc	⏳ 🧪 api-ios	🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	🛠 tv	⏳ 🧪 mac-AS-debug-wk2	🧪 gtk-wk2
	🛠 tv-sim		🧪 api-gtk
	🛠 watch		✅ 🛠 jsc-armv7
	✅ 🛠 watch-sim		⏳ 🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on current version of this PR (hash 9f34acf)

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	✅ 🧪 api-wpe
	🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-skia
🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	🛠 tv	✅ 🧪 mac-AS-debug-wk2	⏳ 🧪 gtk-wk2
	✅ 🛠 tv-sim		⏳ 🧪 api-gtk
✅ 🛠 🧪 merge	🛠 watch		✅ 🛠 jsc-armv7
	✅ 🛠 watch-sim		🧪 jsc-armv7-tests

[webkit-commit-queue]

Committed 276571@main (8025107): https://commits.webkit.org/276571@main

Reviewed commits have been landed. Closing PR #26325 and removing active labels.