Ports the Gecko fixup for text-combine-upright writing mode to Servo. In
addition, this passes the current pseudo element (if any) down to the cascade
for use during the fixup process.
MozReview-Commit-ID: BkHd4AvSsOt
Introduce ComputeDistance trait, which implement compute_distance and
compute_squared_distance.
For vector, compute_squared_distance is necessary because we use Euclidean
distance as the distance between two values. The easier way to implement
compute_squared_distance is to square the result from compute_distance, but
for some property values, they may have many components, e.g. (v1, v2, v3).
If we just square the result from compute_distance, the computation is
(sqrt(v1^2 + v2^2 + v3^2))^2. There are two redundant operators:
"square-root" and then "square". In order to avoid this, we should
implement compute_squared_distance separately for these types.
MozReview-Commit-ID: LmmrUXYlDb6
Remove comment about text-combine-upright digits.
The digits value was never implemented and was dropped from the spec. Old issues like #13769 still discussed if this value should be implemented.
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This version enables [struct field reordering][1] which brings the size
of the types for specified values of some CSS properties under the threshold
such that they shouldn’t be boxed anymore, making unit tests fail.
Simply unboxing them moves the test failure to Stylo’s unit tests,
since the stable compiler used in that case does not do field re-ordering.
Therefore, we manually reorder a couple fields to effectively bring this
optimization to older compilers for a few specific types.
[1]: https://github.com/rust-lang/rust/pull/40377
To make it possible to check the rule type when parsing lengths, we need to pass
the `ParserContext` down through many layers to the place where length units are
parsed.
This change leaves it unused, so it's only to prepare for the next change.
MozReview-Commit-ID: 70YwtcCxnWw
The computed value of word-spacing is T(pub Option<LengthOrPercentage>),
the computed value of letter-spacing is similar to this, T(pub Option<Au>).
It would be nice to have re-usable macro for these kind of struct.
animation_type takes following values:
animation_type="none" for non-animatable properties
animation_type="normal" for animatable properties
animation_type="discrete" for animatable but discrete type of animations
We use string value to distinguish the case where no animation_type is
specified.
animation_type="discrete" will be used in a subsequent patch to make a property
animatable as discrete type.
