Auto merge of #25271 - asajeffrey:gstplugin-glthread, r=Manishearth
Auto merge of #25271 - asajeffrey:gstplugin-glthread, r=Manishearth

Run GL commands on the GStreamer GL thread

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GStreamer has thread affinity for GL contexts.

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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 #25268
- [x] These changes do not require tests because

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