Adjust gstreamer plugins for UWP.
This excludes a set of plugins and dependencies that are currently built with MinGW and will therefore cause WACK errors. The resulting set of plugins loaded by the UWP app are still not UWP-clean, but this makes it much easier to switch over to UWP-clean binaries in the future.
These changes also allow the HoloLens 2 app to start and load again after #23712.
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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#23757
- [x] These changes do not require tests because no tests for windows or UWP.
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Remove canvas->compositing dependency
There's one tiny place in the canvas crate that depends on the compositing crate, and it's really quite backwards. If we use trait objects instead it becomes much cleaner to reason about.
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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 no tests for windows-only webgl code.
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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
<!-- Please describe your changes on the following line: -->
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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