Auto merge of #23857 - asajeffrey:webxr-sessions-track-draw-texture, r=Manishearth

WebXR sessions track draw texture

<!-- Please describe your changes on the following line: -->

Send the XR framebuffer texture to the XR session.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because we don't have webxr reftests

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tests/wpt/metadata/webxr/xrBoundedReferenceSpace_updates.https.html.ini

@@ -1,5 +1,5 @@
 [xrBoundedReferenceSpace_updates.https.html]
-  expected: TIMEOUT
+  expected: ERROR
   ['XRBoundedReferenceSpace updates properly when the changes are applied]
     expected: TIMEOUT
 

tests/wpt/metadata/webxr/xrSession_end.https.html.ini

@@ -1,5 +1,4 @@
 [xrSession_end.https.html]
-  expected: ERROR
   [end event fires when non-immersive session ends]
-    expected: NOTRUN
+    expected: FAIL
 

tests/wpt/metadata/webxr/xrSession_input_events_end.https.html.ini

@@ -1,5 +1,4 @@
 [xrSession_input_events_end.https.html]
-  expected: ERROR
   [Calling end during an input callback stops processing at the right time]
     expected: FAIL
 

tests/wpt/metadata/webxr/xrSession_prevent_multiple_exclusive.https.html.ini

@@ -1,4 +0,0 @@
-[xrSession_prevent_multiple_exclusive.https.html]
-  [Test prevention of multiple simultaneous immersive sessions]
-    expected: FAIL
-