Auto merge of #19388 - BorisChiou:stylo/dommatrix/parser, r=emilio,heycam

stylo: Implement Servo_ParseTransformIntoMatrix

This is an inter-dependent patch of Bug 1408310.

DOMMatrix needs to convert a specified transform list into a matrix, so we rewrite
to_transform_3d_matrix by generics for both specified and computed transform lists.

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [Bug 1408310](https://bugzilla.mozilla.org/show_bug.cgi?id=1408310).
- [X] These changes do not require tests because we can count on the wpt tests for DOMMatrix on Gecko side.

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -65189,11 +65189,11 @@
    "support"
   ],
   "css/transform_skew_a.html": [
-   "8ae3384ece6fc2ebd537736e63723e12b974fff3",
+   "521496ff3fb82a34498d313c1d600a6ca271b1ed",
    "reftest"
   ],
   "css/transform_skew_ref.html": [
-   "6f5154aef6acf1428ac391f0d2dbb2e369ca930b",
+   "a941cd3a8c968494f292ddadd28de5b541ad71b2",
    "support"
   ],
   "css/transform_stacking_context_a.html": [

tests/wpt/mozilla/meta/css/transform_skew_a.html.ini

@@ -1,4 +0,0 @@
-[transform_skew_a.html]
-  type: reftest
-  expected:
-    if os == "linux": FAIL

tests/wpt/mozilla/tests/css/transform_skew_a.html

@@ -18,7 +18,7 @@ div>div {
 }
 
 .transformed1 {
-    transform: skewX(0.3rad);
+    transform: skewX(0.25rad);
 }
 
 .transformed2 {
@@ -26,7 +26,7 @@ div>div {
 }
 
 .transformed3 {
-    transform: skew(0.3rad, 0.5rad);
+    transform: skew(0.25rad, 0.5rad);
 }
 </style>
 </head>

tests/wpt/mozilla/tests/css/transform_skew_ref.html

@@ -17,7 +17,7 @@ div>div {
 }
 
 .transformed1_ref {
-    transform: matrix(1, 0, 0.30933624961, 1, 0, 0);
+    transform: matrix(1, 0, 0.25534192122, 1, 0, 0);
 }
 
 .transformed2_ref {
@@ -25,7 +25,7 @@ div>div {
 }
 
 .transformed3_ref {
-    transform: matrix(1, 0.54630248984, 0.30933624961, 1, 0, 0);
+    transform: matrix(1, 0.54630248984, 0.25534192122, 1, 0, 0);
 }
 
 </style>