Make list-style-type animatable
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stylo: Bug 1374233 - Clamp interpolated values for properties which need to be restricted
Some properties only accept non-negative values, or values greater than or equal to one. It is possible to produce an negative interpolated values while using negative timing functions, so we have to apply a restriction to these values to avoid getting invalid values.
For example, line-height must be non-negative, but the output progress of some timing functions (e,g. cubic-bezier(0.25, -2, 0.75, 1)) may be a negative value, so the interpolated result of line-height is also negative.
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- [X] These changes fix Bug 1374233.
- [X] These changes do not require tests because we have tests in Gecko side already.
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BorderCornerRadius should always be non-negative, so we can implemennt
ToAnimatedValue for it directly, for properties:
1. border-{*}-radius
2. -moz-outline-{*}-radius
MozReview-Commit-ID: HEbeHz9Hfkd
We already have NonNegativeLength and NonNegativeAu, so we can re-use it
to define the specified value and the computed value of border-spacing.
And then implement ToAnimatedValue for it.
MozReview-Commit-ID: CLckpKMYVXU
Add NonNegativeLength, which could be computed to NonNegativeAu. So we
can declare Either<NonNegativeLength, X>, X=Auto, Normal, or Number.
NonNegativeLengthOrAuto is for column-width.
NonNegativeLengthOrNormal is for column-gap.
NonNegativeLengthOrNumber is for -moz-tab-size.
MozReview-Commit-ID: AfU8XpA1um0
Add values::computed::NonNegativeAu, so BorderSideWith could be computed
to this non-negative Au, for the following properties:
1. outline-width
2. border-{*}-width
3. column-rule-width
4. -webkit-text-stroke-width
MozReview-Commit-ID: ASHaB2F7VtM
NonNegativeNumber: for -moz-box-flex, flex-grow, and flex-shrink.
GreaterThanOrEqualToOneNumber: for stroke-miterlimit.
MozReview-Commit-ID: Kgbt99BPdVA
The concept of inherited style is about to get a bit more complicated, and this
will prevent consumers from doing it wrong.
Part 1 of Gecko bug1382806. r=emilio
More grid serialization and parsing fixes
These are the bugs I discovered while I was re-enabling the disabled grid mochitests. Now all grid mochitests are passing! Additionally I converted `Vec<CustomIdent>`'s into `Box<[CustomIdent]>`. We are storing so many line names in vectors. These should help a bit.
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We have checks for these in the shorthand parsing side actually.
But if we need to serialize a group of longhand sub-properties for the shorthand,
we should be able to fail for invalid grammar gracefully. This patch adds these checks.
