Auto merge of #18168 - mantaroh:stroke-distance, r=nox

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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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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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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components/style/values/computed/mod.rs

@@ -369,7 +369,7 @@ impl From<GreaterThanOrEqualToOneNumber> for CSSFloat {
 
 #[allow(missing_docs)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-#[derive(Clone, Copy, Debug, PartialEq, ToCss)]
+#[derive(Clone, ComputeSquaredDistance, Copy, Debug, PartialEq, ToCss)]
 pub enum NumberOrPercentage {
     Percentage(Percentage),
     Number(Number),