Stylist accessors
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Add accessor methods for the `device` and `ruleset` fields in the `Stylist` struct.
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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
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#16788
- [X] These changes do not require tests because it's for stylo
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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.
This enum type used to contain the result of parsing
one CSS source declaration (`name: value;`) and expanding shorthands.
Enum types are as big as the biggest of their variant (plus discriminant),
which was quite big because some shorthands
expand to many longhand properties.
This type was returned through many functions and methods,
wrapped and rewrapped in `Result` with different error types.
This presumably caused significant `memmove` traffic.
Instead, we now allocate an `ArrayVec` on the stack
and pass `&mut` references to it for various functions to push into it.
This type is also very big, but we never move it.
We still use an intermediate data structure because we sometimes decide
after shorthand expansion that a declaration is invalid after all
and that we’re gonna drop it.
Only later do we push to a `PropertyDeclarationBlock`,
with an entire `ArrayVec` or nothing.
In future work we can try to avoid a large stack-allocated array,
and instead writing directly to the heap allocation
of the `Vec` inside `PropertyDeclarationBlock`.
However this is tricky:
we need to preserve this "all or nothing" aspect
of parsing one source declaration,
and at the same time we want to make it as little error-prone as possible
for the various call sites.
`PropertyDeclarationBlock` curently does property deduplication
incrementally: as each `PropertyDeclaration` is pushed,
we check if an existing declaration of the same property exists
and if so overwrite it.
To get rid of the stack allocated array we’d need to somehow
deduplicate separately after pushing multiple `PropertyDeclaration`.
stylo: Continue to propagate quirks mode information to Servo
r=bholley in bugzilla
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stylo: Propagate quirks mode information from Gecko to Servo
r=bholley in bugzilla
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- [X] These changes fix [Bug 1360488](https://bugzilla.mozilla.org/show_bug.cgi?id=1360488)
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