Stylist accessors
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Add accessor methods for the `device` and `ruleset` fields in the `Stylist` struct.
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Refactor grid style types and impls
Fixes#16949.
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Prefixed intrinsic size value
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This is a PR for https://bugzilla.mozilla.org/show_bug.cgi?id=1355402
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In some cases, e.g. mouse event, we need to request an animation-only restyle
to force flush all throttled animations when we handle an event with
coordinates. This restyle shouldn't trigger a normal restyle, and add a
different traversal flag, TraversalRestyleBehavior::ForAnimationOnly, to check.
We add one FFI, Servo_GetProperties_Overriding_Animation, which calls
StrongRuleNode::get_properties_overriding_animations() to get a LonghandIdSet,
which may override animation properties running on compositor.
Allow -moz-stack-sizing to work in a single direction only.
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https://bugzilla.mozilla.org/show_bug.cgi?id=1364115https://reviewboard.mozilla.org/r/138434/
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Stylo: Add support for grid-template-{rows,columns}
This has the implementation of grid's `<track-list>` nightmare.
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Check snapshot id/class flags before looking for those attributes.
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Most elements don't have classes or IDs.
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