Auto merge of #20615 - KiChjang:window-indexed-getter, r=emilio

Implement window indexed getter

Fixes #4589.

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tests/wpt/metadata/css/cssom-view/elementFromPoint.html.ini

@@ -1,7 +1,4 @@
 [elementFromPoint.html]
-  [co-ordinates larger than the viewport from in iframe]
-    expected: FAIL
-
   [SVG element at x,y]
     expected: FAIL
 

tests/wpt/metadata/css/cssom-view/elementsFromPoint.html.ini

@@ -1,13 +1,7 @@
 [elementsFromPoint.html]
-  [co-ordinates larger than the viewport from in iframe]
-    expected: FAIL
-
+  type: testharness
   [SVG element at x,y]
     expected: FAIL
-
   [transformed element at x,y]
     expected: FAIL
 
-  [no hit target at x,y]
-    expected: FAIL
-

tests/wpt/metadata/css/cssom-view/matchMedia.xht.ini

@@ -1,5 +1,20 @@
 [matchMedia.xht]
   type: testharness
-  [CSS Test: CSSOM View matchMedia and MediaQueryList]
+  expected: TIMEOUT
+  [window.matchMedia exists]
     expected: FAIL
+  [MediaQueryList.matches for "(max-width: 199px), all and (min-width: 200px)"]
+    expected: FAIL
+  [MediaQueryList.matches for "(min-aspect-ratio: 1/1)"]
+    expected: FAIL
+  [MediaQueryList.matches for "(width: 200px)"]
+    expected: FAIL
+  [MediaQueryList.matches for "(min-width: 150px)"]
+    expected: FAIL
+  [Resize iframe from 200x100 to 200x50, then to 100x50]
+    expected: NOTRUN
+  [Listeners are called in the order which they have been added]
+    expected: NOTRUN
+  [Listener added twice is only called once.]
+    expected: NOTRUN