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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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#23742
- [x] There are tests for these changes
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[hololens] More events, remove most of the statics, better shutdown
Depends on #23831
- Buttons are greyed out when necessary
- Reload, Stop, Back and Fwd are properly bound
- Servo.cpp rewritten in a much cleaner way
- Removed most of the statics
- Improved (but not full) shutdown
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Make Windows arm64 easy
* Add a ServoApp project configuration
* Add a `--win-arm64` build flag (now `python mach build -r --win-arm64 --uwp`)
* Automatically set up GStreamer LIB environment
* Yell if the cross-compilation environment isn't set up correctly
* Automatically find the Visual C++ installation for DLL packaging, rather than relying on an environment variable
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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#23793 and fix#23795
- [x] There are tests for these changes
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Add source module to UWP logging output
Updated support/hololens/Servo.cpp to use url: google.com
New debug output:
```
RUST: DEBUG - html5ever::tokenizer - got characters None
RUST: DEBUG - script::script_thread - Processing event FromConstellation(ConstellationControlMsg::NavigationResponse).
RUST: DEBUG - html5ever::tokenizer - processing in state RawData(ScriptData)
```
---
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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#23755
- [x] These changes do not require tests because we can't automatically test logging output.
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Magic Leap developer ergonomic improvements
These changes allow passing in command line arguments for Servo via a SERVO_ARGS from the mldb terminal when launching the activity, as well as passing in a launch URL as an argument. It also redirects stdout to the ML log, which allows observing the built-in profiler output.
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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#23041
- [x] These changes do not require tests because no magic leap testing.
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Support for ExternalVR implementation
This PR adds the hook necessary for the ExternalVR rust-webvr driver.
Waiting on rust-webvr 0.9.3 to be published before landing.
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Fix daydream support
Added a googlevr-flavor AndroidManifest.xml for servoapp (this gets
merged with the main one). Daydream works now.
I haven't added an oculus one since as far as I can tell we don't
support pure servo on oculus yet.
r? @jdm @paulrouget
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