Crash observed in running webxr layout test from WebCore::WebXRSession::~WebXRSession()

[obyknovenius]

75f9692

Crash observed in running webxr layout test from WebCore::WebXRSession::~WebXRSession()
https://bugs.webkit.org/show_bug.cgi?id=272426

Reviewed by Mike Wyrzykowski.

Since `SimulatedXRDevice` inherits from `PlatformXR::Device` which is
reference counted, `WebFakeXRDevice::m_device` should be a `Ref`.

* Source/WebCore/testing/WebFakeXRDevice.cpp:
(WebCore::WebFakeXRDevice::WebFakeXRDevice):
(WebCore::WebFakeXRDevice::setViews):
(WebCore::WebFakeXRDevice::setViewerOrigin):
(WebCore::WebFakeXRDevice::simulateVisibilityChange):
(WebCore::WebFakeXRDevice::setFloorOrigin):
(WebCore::WebFakeXRDevice::simulateInputSourceConnection):
(WebCore::WebFakeXRDevice::setSupportsShutdownNotification):
(WebCore::WebFakeXRDevice::simulateShutdown):
* Source/WebCore/testing/WebFakeXRDevice.h:

Canonical link: https://commits.webkit.org/277983@main

67d1497

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
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 67d1497)

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
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 277983@main (75f9692): https://commits.webkit.org/277983@main

Reviewed commits have been landed. Closing PR #27735 and removing active labels.