Bug 1712196 [wpt PR 29063] - WindowProperties returns WindowProxy for named <iframe>s, a=testonly

Automatic update from web-platform-tests
WindowProperties returns WindowProxy for named <iframe>s (#29063)

Follow-up of #27970.
--

wpt-commits: 75113f4a0087051b8065cc21ef7ef980ba10b265
wpt-pr: 29063

testing/web-platform/tests/html/browsers/the-window-object/named-access-on-the-window-object/window-named-properties.html

@@ -60,7 +60,7 @@ test(function() {
 }, "constructor");
 test(function() {
   var gsp = Object.getPrototypeOf(Object.getPrototypeOf(window));
-  assert_equals(gsp.baz, document.getElementsByTagName("iframe")[1]);
+  assert_equals(gsp.baz, document.getElementsByTagName("iframe")[1].contentWindow);
 }, "duplicate property names")
 var t = async_test("Dynamic name")
 var t2 = async_test("Ghost name")