Upgrade WebRender
This is against an old Servo because I can't build current Servo due to compile errors in RNG crates. I verified that it starts up.
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- [x] These changes fix#23516
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Sync WebIDL.py with gecko
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The new change requires default dictionary value for optional dictionary-type arguments.
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- [x] These changes fix#23703
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Use new WebXR API in script
Todo:
- [x] Hook new `Frame` information into `XRFrame`
- [x] Make spaces use new transform info
- [x] Hook up session view metadata correctly
- [x] Get mocking working again
- [x] Get inputs working
Optional todos:
- [x] Add support for active and animationFrame bool on XRFrame
- [x] Correctly handle viewer and offset spaces instead of casting
- [x] Error on zero-length quaternions
<s>Not really ready for review yet, but you can go ahead and review what I have so far. It doesn't do anything yet, aside from crash horribly. I'm opening this PR early so i have a place to track progress.</s>
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Load GST videofilter plugins.
The video playback tries to create a videobalance element and can't find it without this plugin.
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WebGLSender doesn't really implement Serializable
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Add an API which turns a `WebGLSender` into something that is actually serializable.
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Add clipboard cut functionality
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This PR adds clipboard cut functionality. #23735
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