Auto merge of #23973 - emilio:gecko-sync, r=emilio,jdm

style: Sync changes from mozilla-central.

See each individual commit for details.

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tests/wpt/metadata/css/css-fonts/font-weight-xxx-large.html.ini

@@ -1,2 +0,0 @@
-[font-weight-xxx-large.html]
-  expected: FAIL

tests/wpt/metadata/css/css-fonts/parsing/font-size-valid.html.ini

@@ -1,4 +0,0 @@
-[font-size-valid.html]
-  [e.style['font-size'\] = "xxx-large" should set the property value]
-    expected: FAIL
-

tests/wpt/metadata/html/rendering/widgets/button-layout/display-other.html.ini

@@ -44,9 +44,6 @@
   [display: table-row-group]
     expected: FAIL
 
-  [display: flow]
-    expected: FAIL
-
   [display: table-column-group]
     expected: FAIL