Auto merge of #25734 - pylbrecht:get.transform, r=jdm

Implement CanvasRenderingContext2D.getTransform()

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- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix part of #25331

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- [x] There are tests for these changes

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components/script/dom/webidls/CanvasRenderingContext2D.webidl

@@ -59,7 +59,7 @@ interface mixin CanvasTransform {
                  unrestricted double e,
                  unrestricted double f);
 
-  // [NewObject] DOMMatrix getTransform();
+  [NewObject] DOMMatrix getTransform();
   void setTransform(unrestricted double a,
                     unrestricted double b,
                     unrestricted double c,

components/script/dom/webidls/DOMMatrix.webidl

@@ -10,7 +10,7 @@
  * related or neighboring rights to this work.
  */
 
-[Exposed=(Window,Worker),
+[Exposed=(Window,Worker,PaintWorklet),
  LegacyWindowAlias=WebKitCSSMatrix]
 interface DOMMatrix : DOMMatrixReadOnly {
     [Throws] constructor(optional (DOMString or sequence<unrestricted double>) init);

components/script/dom/webidls/DOMMatrixReadOnly.webidl

@@ -10,7 +10,7 @@
  * related or neighboring rights to this work.
  */
 
-[Exposed=(Window,Worker)]
+[Exposed=(Window,Worker,PaintWorklet)]
 interface DOMMatrixReadOnly {
     [Throws] constructor(optional (DOMString or sequence<unrestricted double>) init);
 

components/script/dom/webidls/DOMPoint.webidl

@@ -10,7 +10,7 @@
  */
 
 // http://dev.w3.org/fxtf/geometry/Overview.html#dompoint
-[Exposed=(Window,Worker)]
+[Exposed=(Window,Worker,PaintWorklet)]
 interface DOMPoint : DOMPointReadOnly {
     [Throws] constructor(optional unrestricted double x = 0, optional unrestricted double y = 0,
                 optional unrestricted double z = 0, optional unrestricted double w = 1);

components/script/dom/webidls/DOMPointReadOnly.webidl

@@ -10,7 +10,7 @@
  */
 
 // http://dev.w3.org/fxtf/geometry/Overview.html#dompointreadonly
-[Exposed=(Window,Worker)]
+[Exposed=(Window,Worker,PaintWorklet)]
 interface DOMPointReadOnly {
     [Throws] constructor(optional unrestricted double x = 0, optional unrestricted double y = 0,
                 optional unrestricted double z = 0, optional unrestricted double w = 1);