Auto merge of #18750 - Manishearth:transform-generic, r=emilio,xidorn

Make transforms generic

This makes the specified and computed value of transform share a generic
backing enum.

This will eventually be a complete fix for
https://bugzilla.mozilla.org/show_bug.cgi?id=1391145 , and also
incidentally fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1405881

Currently WIP -- the generic transform exists and is used, but this
currently misses some animation and glue cases.

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tests/wpt/metadata/css/css-transforms/2d-rotate-js.html.ini

@@ -1,8 +0,0 @@
-[2d-rotate-js.html]
-  type: testharness
-  [this should make a small green square rotated 30 degrees, and the browser should return the rotation as 30 degrees as the computed value NOT a matrix]
-    expected: FAIL
-
-  [JS test: Rotate via javascript must show the correct computed rotation]
-    expected: FAIL
-

tests/wpt/metadata/css/css-transforms/transform-2d-getComputedStyle-001.html.ini

@@ -11,7 +11,3 @@
 
   [Matrix for skew]
     expected: FAIL
-
-  [Matrix for general transform]
-    expected: FAIL
-

tests/wpt/metadata/css/css-transforms/transform_translate_invalid.html.ini

@@ -1,5 +0,0 @@
-[transform_translate_invalid.html]
-  type: testharness
-  [transform_translate_null_null]
-    expected: FAIL
-

tests/wpt/metadata/css/css-transforms/transform_translate_max.html.ini

@@ -1,5 +0,0 @@
-[transform_translate_max.html]
-  type: testharness
-  [transform_translate_max]
-    expected: FAIL
-

tests/wpt/metadata/css/css-transforms/transform_translate_min.html.ini

@@ -1,5 +0,0 @@
-[transform_translate_min.html]
-  type: testharness
-  [transform_translate_min]
-    expected: FAIL
-