Add a pref to indicate user intent to enter webxr
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Add a pref to indicate that the user has indicated intent to enter webxr.
---
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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 it's a command-line pref
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Compile external scripts off the main thread
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---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix#26571 (GitHub issue number if applicable)
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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___
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Add stubs for HTMLCanvasElement.captureStream and WebRTC transceiver APIs
These stubs are hidden by default and only exist to allow getting past the relevant code that invokes them on hubs.mozilla.org.
Add a sessionavailable event that allows content to enter an XR session without a user gesture
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This allows servo to implement immersive web apps. https://immersive-web.github.io/webxr/#application-launch
---
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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 I'm not sure we should have a WPT for something this non-standard.
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Remove support for energy and heartbeats profiling
Both are disabled by default (energy at compile-time, heartbeats with a run-time option). Neither is tested of CI. Neither has been used in a long time. They might have Undefined Behavior: https://github.com/servo/servo/issues/26550#issuecomment-634238098. They each depend on a mostly-unmaintained C library. The thread-safety expectation of those libraries are unknown.
Add VTTRegion and part of VTTCue DOM interfaces
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Hello! In this PR I implemented the VTTRegion DOM interface and part of VTTCue (#22312). Before continuing I thought it's maybe a good idea to first request a review or even merge what I did up to this point, as I might get stuck on the next part. I have a slight idea of what needs to be done (I assume it's hooking the GStreamer parser somewhere in `GetCueAsHTML()`), but a short outline or some more instructions would help a lot.
I updated test expectations by first running:
```
./mach test-wpt tests/wpt/web-platform-tests/webvtt/api --log-raw servo.log --pref dom.webvtt.enabled=true
```
then
```
./mach update-wpt servo.log
```
Thanks!
---
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- [ ] These changes fix #___ (GitHub issue number if applicable)
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The angle and disable-vsync options were declared as global options but
only used in the Glutin embedding for desktop builds. Moving them to
the Glutin embedding code makes them easier to update.
Partially fixes#23009
