Add libxcb dependencies to README and bootstrap.py
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Gets servo to build on Ubuntu xenial+ again.
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Use backtrace fork with UWP-specific fix.
Fixes#27367, which was introduced by 57f4f0a09f. I'd like to do a new release in the store, and I would prefer not to wait for a new version of backtrace to be released before that can happen.
build(deps): bump crossbeam-channel from 0.4.2 to 0.4.3
Bumps [crossbeam-channel](https://github.com/crossbeam-rs/crossbeam) from 0.4.2 to 0.4.3.
<details>
<summary>Commits</summary>
<ul>
<li><a href="5a68889cbc"><code>5a68889</code></a> Bump crossbeam-channel to v0.4.3</li>
<li><a href="669736b8e5"><code>669736b</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/537">#537</a> from nical/cb-chan-license</li>
<li><a href="ce713a1f8b"><code>ce713a1</code></a> Change crossbeam-channel's license to MIT OR Apache-2.0.</li>
<li><a href="81ab18efc7"><code>81ab18e</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/530">#530</a> from crossbeam-rs/license</li>
<li><a href="81eea47889"><code>81eea47</code></a> Remove parentheses from license field in Cargo.toml</li>
<li><a href="2f1ed42da6"><code>2f1ed42</code></a> Merge <a href="https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/527">#527</a></li>
<li><a href="1ad6b9fdd4"><code>1ad6b9f</code></a> Attempt to fix permission error</li>
<li><a href="af63c6b605"><code>af63c6b</code></a> Propagate nightly feature</li>
<li><a href="cae71e1c62"><code>cae71e1</code></a> Check all feature combinations works properly on CI</li>
<li><a href="bbc8601e4d"><code>bbc8601</code></a> Merge <a href="https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/525">#525</a> <a href="https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/528">#528</a></li>
<li>Additional commits viewable in <a href="https://github.com/crossbeam-rs/crossbeam/compare/v0.4.2...crossbeam-channel-0.4.3">compare view</a></li>
</ul>
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Compile external scripts off the main thread
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Implement GPUCommandEncoder.copy commands
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r?@kvark
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UWP: non random port for devtools, and support for custom UWP prefs
packages-prefs.json is now taken into account for libsimpleservo. Making it possible to have custom pref for the UWP builds, removing some weirdness in the way we handle preferences in the hololens code.
This also adds a new set of preferences to control the devtools server startup state, and make the port choice constant across sessions.
Fix#27267Fix#22970
Update XRWebGLLayer to match specification.
This unbreaks most of the webxr WPT tests.
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- [x] These changes fix#27312
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Implement core float layout for layout 2020
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Add an implementation of the core float and clear placement logic in layout 2020, not yet wired to the rest of layout.
This commit implements an object that handles the 10 rules in CSS 2.1:
https://www.w3.org/TR/CSS2/visuren.html#float-position
The implementation strategy is that of a persistent balanced binary search tree
of float bands. Binary search trees are commonly used for implementing float
positioning; e.g. by WebKit. Persistence enables each object that interacts
with floats to efficiently contain a snapshot of the float list at the time
that object was laid out. That way, incremental layout can invalidate and start
reflow at any point in a containing block.
This commit features extensive use of
[QuickCheck](https://github.com/BurntSushi/quickcheck) to ensure that the rules
of the CSS specification are followed.
Because this is not yet connected to layout, floats will not actually be laid
out in Web pages yet.
Note that unit tests as set up in Servo currently require types that they
access to be public. Therefore, some internal layout 2020 types that were
previously private have been made public. This is somewhat unfortunate.
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Update GPUObjectBase webidl and cleanup valid flags
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Update labels to be `USVString`
Remove `valid` flags in WebGPU resources. The only place where we still have that is `GPUCommandEncoder` (Only to validate the GPUCommandEncoder state. Not sure how errors would be handled/reported by server for copy commands).
r?@kvark
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2020, not yet wired to the rest of layout.
This commit implements an object that handles the 10 rules in CSS 2.1:
https://www.w3.org/TR/CSS2/visuren.html#float-position
The implementation strategy is that of a persistent balanced binary search tree
of float bands. Binary search trees are commonly used for implementing float
positioning; e.g. by WebKit. Persistence enables each object that interacts
with floats to efficiently contain a snapshot of the float list at the time
that object was laid out. That way, incremental layout can invalidate and start
reflow at any point in a containing block.
This commit features extensive use of
[QuickCheck](https://github.com/BurntSushi/quickcheck) to ensure that the rules
of the CSS specification are followed.
Because this is not yet connected to layout, floats will not actually be laid
out in Web pages yet.
Note that unit tests as set up in Servo currently require types that they
access to be public. Therefore, some internal layout 2020 types that were
previously private have been made public. This is somewhat unfortunate.
Part of #25167.
