Use exhaustive match for cloning keyword value by default for property using enum class
rather than casting them to `u8` then do inexhaustive match.
I don't see why we couldn't do this.
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First, we define computed::CSSPixelLength which contains a CSSFloat, a
pixel value, and then we replace computed::Length with CSSPixelLength.
Therefore, the |ComputedValue| of NoCalcLength, AbsoluteLength,
FontRelativeLength, ViewportPercentageLength, CharacterWidth, and
PhysicalLength is CSSPixelLength.
Besides, we drop NonNegativeAu, and replace computed::NonNegativeLength
with NonNegative<computed::Length>. (i.e. NonNegative<CSSPixelLength>)
Support None and NotSet for the fallback type of SVGPaint.
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We didn't set None and NotSet for the fallback type of SVGPaint, and it caused the fallback color is wrong when fallback color is empty or keyword `none`. So, we add the None and NotSet support for it.
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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.
Make content animatable
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column-count should be greater than or equal to 1. Also it should be less than
or equal to nsStyleColumn_kMaxColumnCount since we limit it in
set_column_count().
Make -moz-appearance animatable
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Move percentage to mod.rs
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The tests in the issue worked for me locally.
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