Remove GStreamer dependencies from UWP app.
Remove all GStreamer dependencies and restore MSVC CRT dependencies to allow running the UWP on non-desktop devices.
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It's impossible to conditionally use a crate based only on cargo features, so
temporarily disable the backend on all Windows builds while we sort out how
to get the UWP builds working again.
WebXr: allow for only a single raf message, until callbacks execute
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See https://github.com/servo/webxr/issues/34
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Stylo: replace product={gecko,servo} with engine={gecko,servo-2013,servo-2020}
Renaming the variable helped make sure I looked at every use.
Also auto-generate relevant parts of `CSSStyleDeclaration.webidl`, to make libscript compile accordingly.
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Use origin of final HTTP response as document origin
I discovered surprising problems when loading pages from http://joshmatthews.net that load same-origin images and try to use them as webgl textures. Since there's a redirect from joshmatthews.net to www.joshmatthews.net, the images are not considered same-origin in Servo because the document stores the origin for the original request's URL, rather than the origin of the response that is received after processing any redirections.
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Avoid panic during shutdown when Blobs exist
Observed when closing the UWP app when https://www.joshmatthews.net/demos/lamp.html is the active document.
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Don't panic if WebGL thread can't be reached during finalization.
Before these changes, when closing a browsing instance displaying WebGL content I would hit a bunch of panics when the WebGL objects are GCed after the WebGL thread has shut down. With these changes shutdown is panic-free.
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Drop webgl main thread data during shutdown.
Before this change I get a panic late in shutdown because we end up trying to communicate with webrender during TLS teardown.
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Fix ARM64 app startup
I missed a DLL in the ARM64 app configuration, so currently it fails to start up. With this change I verified that https://joshmatthews.net/osc.html and https://joshmatthews.net/mp3.html produce audio output on a Windows arm64 laptop.
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- [x] These changes do not require tests because no windows arm64 CI.
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WebXR sessions track draw texture
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Send the XR framebuffer texture to the XR session.
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Various UWP GStreamer improvements
There are a number of positive changes in these commits:
* we successfully load GStreamer plugins in ARM64 UWP builds
* we correctly link the ARM64 ANGLE libraries when appropriate
* it is no longer necessary to manually set the LIB environment variable on Windows
* we automatically download and link against UWP-friendly GStreamer binaries when building with `--uwp`
* the use of vcruntime140.dll, msvcp140.dll and api-ms-win-crt-runtime-l1-1-0.dll in the UWP application has been removed and the build does not repackage them
* the set of base supporting GStreamer DLLs has been expanded to allow the gstlibav plugin to load correctly
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Replace use of callbacks in webxr by channels
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Use senders rather than callbacks in webxr.
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When using the WebGL external image API, use sync calls if we happen to be on the WebGL thread
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When using the external image API, use synchronous method calls if we happen to be on the same thread as WebGL.
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- [x] These changes fix#23832 hopefully
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