Auto merge of #11214 - farodin91:windowproxy, r=jdm

Support WindowProxy return values in bindings

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --faster` does not report any errors
- [x] These changes fix #10965 (github issue number if applicable).

Either:
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

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tests/wpt/metadata/html/browsers/the-window-object/window-properties.html.ini

@@ -297,15 +297,9 @@
   [Window attribute: onwaiting]
     expected: FAIL
 
-  [Window unforgeable attribute: window]
-    expected: FAIL
-
   [Window unforgeable attribute: location]
     expected: FAIL
 
-  [Window unforgeable attribute: top]
-    expected: FAIL
-
   [Window replaceable attribute: self]
     expected: FAIL
 

tests/wpt/metadata/html/dom/interfaces.html.ini

@@ -5304,9 +5304,6 @@
   [Window interface: attribute localStorage]
     expected: FAIL
 
-  [Window interface: window must have own property "window"]
-    expected: FAIL
-
   [Window interface: window must inherit property "self" with the proper type (1)]
     expected: FAIL
 
@@ -5358,9 +5355,6 @@
   [Window interface: window must inherit property "length" with the proper type (19)]
     expected: FAIL
 
-  [Window interface: window must have own property "top"]
-    expected: FAIL
-
   [Window interface: window must inherit property "opener" with the proper type (21)]
     expected: FAIL
 
@@ -9581,4 +9575,3 @@
 
   [HTMLInputElement interface: createInput("button") must inherit property "useMap" with the proper type (57)]
     expected: FAIL
-