WR multi-document update
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The PR updates WR version to support multiple documents (https://github.com/servo/webrender/pull/1509) but doesn't take advantage of this new feature yet.
It also makes Servo to use `DevicePixel` from WR instead of rolling out another one.
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The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
Suppress CSS parser errors for vendor-prefixed properties.
This matches the behaviour of Gecko's CSS parser.
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This allows us to have ensure_data() and clear_data() functions on the TElement
trait, instead of hacking around it adding methods in random traits.
This also allows us to do some further cleanup, which I'd rather do in a
followup.
This reverts commit ebfc8f5858, reversing
changes made to 5585ff2c44.
Animation code can reenter and create a new TLS context from the traversal
SequentialTask, so this won't work as written.
Removed unused import
Removed unused import `script_layout_interface::reporter::CSSErrorReporter in components/layout_thread/lib.rs
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Parallel layout optimizations
This takes some of the optimizations made to parallel styling in #16971 and applies them to parallel layout. Specifically:
* Reduce the chunk size, to increase chances for parallelism on trees with small fan-out.
* Reduce allocations by using SmallVec.
* Reduce task switching by processing up to one chunk of children within the same rayon task as the parent.
This cuts the "Primary Layout Pass" time in **half** on the MySpace page from [tp5n], and on my other real-world test pages it is a small improvement or close to no change.
[tp5n]: https://wiki.mozilla.org/Buildbot/Talos/Tests#tp5n_pages_set
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This commit splits the style and layout data in two separate refcells.
These transmutes have been a source of trouble (for example on Android), and
they feel like a hack anyway.
Fixes#16982
Stylist accessors
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Add accessor methods for the `device` and `ruleset` fields in the `Stylist` struct.
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Renamed constellation::Frame to constellation::BrowsingContext
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Now that script has `WindowProxy` rather than `BrowsingContext` objects, we can rename `Frame` in the constellation to `BrowsingContext`. In particular, this means that `FrameId`s are now `BrowsingContextid`s, which better captures their purpose (and they are used in a lot of places, not just the constellation).
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