Fix DOMMatrix rotate test failure
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Rotation functions have been working backward because of https://github.com/servo/euclid/issues/354, so this temporarily fixes it.
cc @Manishearth
PS: How can I run bors-servo myself?
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Fix panic when running test-background-fetch-permission.html
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* Propagate `Error::JSFailed` in `Permissions::create_descriptor`
* In `Error::to_jsval`, only check if a JS exception is not pending if `self` is not `Error::JSFailed`
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Clipboard refactoring
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This PR removes clipboard handling from the constellation. Instead, now embedder handles it.
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- [X] These changes do not require tests because it is enough to test manually in input box, if copying and pasting still works .
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Get a WebXR device registry to each script thread
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This PR gets an XR device registry to each script thread.
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Add DOMMatrix.prototype.scaleNonUniform
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Implements `scaleNonUniform()` [per the spec](https://drafts.fxtf.org/geometry/#dom-dommatrixreadonly-scalenonuniform).
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WebXR initialization
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Initialize a WebXR device registry in Servo.
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Support DOMMatrix string constructor
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Implemented DOMMatrix string constructor per [the spec](https://drafts.fxtf.org/geometry/#dom-dommatrixreadonly-dommatrixreadonly).
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Pass events loop to glwindow test webvr implementation
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Pass the event loop to the glwindow webvr test device, so it can implement keyboard controls. The matching rust-webvr PR is https://github.com/servo/rust-webvr/pull/84
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Not all cargo subcommands take `--manifest-path`.
Use plain `cargo` instead (rustup reads the `rust-toolchain` file)
or consider adding new mach sub-commands.
Don't process events while borrowing the event loop
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At the moment, the glutin embedder holds onto a borrow of the events loop while processing events, which is dangerous if any of the event handlers end up using the events loop reentrantly. (This caused a panic while integrating https://github.com/servo/rust-webvr/pull/84.)
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Remove passing test
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This was added in #23310. Was that a mistake?
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Support VS Build Tools 2019
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This detects VS Build Tools 2019 installation, which optionally provides VC2017 to be compatible with Servo.
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