Stylo: Change mask-repeat initial value from no-repeat to repeat.
<!-- Please describe your changes on the following line: -->
Change mask-repeat initial value from no-repeat to repeat.
Gecko bug link:
https://bugzilla.mozilla.org/show_bug.cgi?id=1364273
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).
<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->
<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/16864)
<!-- Reviewable:end -->
A specified position is now a struct made of two values of different types,
the first one being PositionComponent<X>, and the second one PositionComponent<Y>.
A position component is represented by the new enum PositionComponent<Side>,
with the three values Center, Length(LengthOrPercentage), and
Side(Side, Option<LengthOrPercentage>).
Side keywords are represented by the X and Y enums, which don't include a value
for the center keyword anymore. They are accompanied by the Side trait, which
allows us to determine whether a side keyword is "left" or "top".
This refactor simplified the parsing and serialisation code and exposed bugs in it,
where it would reject valid <position> values followed by arbitrary tokens,
and where it would fail to prefer "left" to "right" when serialising positions
in basic shapes.
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
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.
It's a bit unfortunate the use separate implementations of SpecifiedUrl for Servo
and Gecko, but they're different enough at this point that I don't think it really
makes sense to try to share everything. Splitting them out has some nice
simplifications as well.
I recognize that there's still some potential correctness issues for Servo using
the resolved URI in various places where the original URI may be the right thing,
but I've got too much on my plate to look into that for now.
MozReview-Commit-ID: BeDu93TQ4Ow