Auto merge of #21045 - jonathanKingston:make-parent-replaceable, r=jdm

Allow window.parent attribute to be replaceable by JavaScript.

Permit JS to override the window.parent attribute.

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- [x] `./mach test-tidy` does not report any errors
- [X] These changes fix #20932 (github issue number if applicable).
- [x] There are tests for these changes OR

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2 files changed, 1 insertions, 4 deletions

diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index 37bba020622..0cda7d2d800 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -38,7 +38,7 @@
   //         attribute any opener;
   // Note that this can return null in the case that the browsing context has been discarded.
   // https://github.com/whatwg/html/issues/2115
-  readonly attribute WindowProxy? parent;
+  [Replaceable] readonly attribute WindowProxy? parent;
   readonly attribute Element? frameElement;
   //WindowProxy open(optional DOMString url = "about:blank", optional DOMString target = "_blank",
   //                 optional DOMString features = "", optional boolean replace = false);
diff --git a/tests/wpt/metadata/html/browsers/the-window-object/window-properties.https.html.ini b/tests/wpt/metadata/html/browsers/the-window-object/window-properties.https.html.ini
index f0c77110ca6..69a79de6c40 100644
--- a/tests/wpt/metadata/html/browsers/the-window-object/window-properties.https.html.ini
+++ b/tests/wpt/metadata/html/browsers/the-window-object/window-properties.https.html.ini
@@ -50,9 +50,6 @@
   [Window replaceable attribute: toolbar]
     expected: FAIL
 
-  [Window replaceable attribute: parent]
-    expected: FAIL
-
   [Window replaceable attribute: external]
     expected: FAIL