Handle single X keyword value in LegacyPosition
This is reviewed by emilio in bugzilla.
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- [X] These changes fix [Bug 1391432](https://bugzilla.mozilla.org/show_bug.cgi?id=1391432)
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We need to use enum instead of Either since we can't interpolate stroke-* between
unitless length and unit length(e.g. '5' -> '10px').
This coomit make following:
* Introduce SVGLengthOrPercentageOrNumber on computed and specified values.
* Make SVGLengthOrPercentageOrNumber animatable.
* Make stroke-dasharray not-accumulate.
Introduce ComputedUrl
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Use the new `ComputedUrl` type for computed types and `SpecifiedUrl` for specified types instead of using the `SpecifiedUrl` implementation for both.
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As silly as it may seem to specify font-sizes using viewport units, we weren't
handling zoom for them correctly either.
Bug: 1388588
Reviewed-by: Manishearth
MozReview-Commit-ID: 3Q6phYAu5CE
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] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [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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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
