Auto merge of #25048 - asajeffrey:gstplugin-glmemory, r=ferjm

GStreamer plugin should use GLMemory

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Get the gstreamer servosrc plugin to generate frames in GLMemory rather than main memory.

---
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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 fix #24831
- [x] These changes do not require tests because it's an embedding perf issue

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etc/taskcluster/decision_task.py

@@ -490,7 +490,9 @@ def windows_unit(cached=True):
             "mach smoketest --angle",
             "mach package --dev",
             "mach build --dev --libsimpleservo",
-            "mach build --dev -p servo-gst-plugin",
+            # We're getting link errors on windows, due to the x11 feature being
+            # enabled on gstreamer-gl. https://github.com/servo/media/pull/304/
+            "mach build --dev --media-stack=dummy -p servo-gst-plugin",
 
         )
         .with_artifacts("repo/target/debug/msi/Servo.exe",