Auto merge of #18234 - BorisChiou:stylo/transform/distance_mismatch, r=birtles,nox

stylo: Bug 1390039 - Implement compute_distance for mismatched transform lists.

Implement ComputeSquaredDistance for mismatched transform lists.
In order to do this, we have to convert a transform list into a 3d matrix,
so I move the code from layout module into style module for reusing it.

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [Bug 1390039](https://bugzilla.mozilla.org/show_bug.cgi?id=1390039).
- [X] These changes do not require tests because this is a Gecko feature and I add many tests in Gecko already.

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components/style/values/computed/angle.rs

@@ -4,6 +4,7 @@
 
 //! Computed angles.
 
+use euclid::Radians;
 use std::{f32, f64, fmt};
 use std::f64::consts::PI;
 use style_traits::ToCss;
@@ -99,3 +100,10 @@ impl ToCss for Angle {
         }
     }
 }
+
+impl From<Angle> for Radians<CSSFloat> {
+    #[inline]
+    fn from(a: Angle) -> Self {
+        Radians::new(a.radians())
+    }
+}