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] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#23516
- [x] There are tests for these changes
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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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- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because this is fixing a panic
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Support WebAudio on Windows
These changes improve the GStreamer experience on Windows in several ways:
* we package the set of plugins and their dependencies that Servo requires for media support
* we explicitly load those plugins when starting the media engine rather than relying on an existing gstreamer installation
These changes do not affect the experience on non-Windows platforms, but the path is clear to do so in order to fix problems like #23519. With these changes I can successfully hear a tone when loading https://joshmatthews.net/osc.html in both a desktop build and a UWP build.
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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#23631 and fix#23698
- [x] These changes do not require tests because no tests on windows ;_;
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