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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- [X] These changes fix [Bug 1380590](https://bugzilla.mozilla.org/show_bug.cgi?id=1380590)
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Reduce usage of fmt in serialization and error reporting
`format!` and `write!` create a somewhat-heavyweight `Formatting` struct and use dynamic dispatch to call into impls of `Dispaly` and related traits. The former also allocates an intermediate string that is sometimes unnecessary.
I started looking into this from https://bugzilla.mozilla.org/show_bug.cgi?id=1355599, but I expect the impact there will be small to insignificant. It might be a slightly less so on parsing (error reporting).
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PR #18103 disallowed interpolation between fill:none and fill:none, but that change was regressed by the refactoring in PR #18239.
This patch restores the intended behavior, disabling animation of SVGPaintKind::None.
Properly set default direction of prefixed linear gradients
The default linear gradient direction is `to bottom`. This correspondes to
`top` keyword in prefixed linear gradients. We should preserve the default value.
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The default linear gradient direction is `to bottom`. This correspondes to
`top` keyword in prefixed linear gradients. We should preserve the default value.
Add ComputeSquaredDistance trait for SvgLengthOrPercentageOrNumber
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This is a PR for https://bugzilla.mozilla.org/show_bug.cgi?id=1387986
This patch will add ComputeSquaredDistance trait for SvgLengthOrPercentageOrNumber in order to calculating distance between LengthOrPercentage and Number.
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There are already these tests in dom/smil/tests of gecko, this PR will enable these tests.
For detail, see https://bugzilla.mozilla.org/show_bug.cgi?id=1387986.
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Currently, Servo uses ComputeSquaredDistance derive for
SvgLengthOrPercentageOrNumber, so servo can't calculate between
LengthOrPercentage and Number.
This PR will allow calculating these value.
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 list-style-type animatable
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NonNegativeNumber: for -moz-box-flex, flex-grow, and flex-shrink.
GreaterThanOrEqualToOneNumber: for stroke-miterlimit.
MozReview-Commit-ID: Kgbt99BPdVA
