Auto merge of #23685 - saschanaz:scalenonuniform, r=paulrouget

Add DOMMatrix.prototype.scaleNonUniform

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Implements `scaleNonUniform()` [per the spec](https://drafts.fxtf.org/geometry/#dom-dommatrixreadonly-scalenonuniform).

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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #23683

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- [x] There are tests for these changes

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components/script/dom/dommatrixreadonly.rs

@@ -571,6 +571,18 @@ impl DOMMatrixReadOnlyMethods for DOMMatrixReadOnly {
             .ScaleSelf(scaleX, scaleY, scaleZ, originX, originY, originZ)
     }
 
+    // https://drafts.fxtf.org/geometry/#dom-dommatrixreadonly-scalenonuniform
+    fn ScaleNonUniform(&self, scaleX: f64, scaleY: f64) -> DomRoot<DOMMatrix> {
+        DOMMatrix::from_readonly(&self.global(), self).ScaleSelf(
+            scaleX,
+            Some(scaleY),
+            1.0,
+            0.0,
+            0.0,
+            0.0,
+        )
+    }
+
     // https://drafts.fxtf.org/geometry-1/#dom-dommatrixreadonly-scale3d
     fn Scale3d(&self, scale: f64, originX: f64, originY: f64, originZ: f64) -> DomRoot<DOMMatrix> {
         DOMMatrix::from_readonly(&self.global(), self).Scale3dSelf(scale, originX, originY, originZ)

components/script/dom/webidls/DOMMatrixReadOnly.webidl

@@ -56,6 +56,8 @@ interface DOMMatrixReadOnly {
                     optional unrestricted double originX = 0,
                     optional unrestricted double originY = 0,
                     optional unrestricted double originZ = 0);
+    [NewObject] DOMMatrix scaleNonUniform(optional unrestricted double scaleX = 1,
+                                          optional unrestricted double scaleY = 1);
     DOMMatrix scale3d(optional unrestricted double scale = 1,
                       optional unrestricted double originX = 0,
                       optional unrestricted double originY = 0,