diff -r 000000000000 -r 6474c204b198 dom/interfaces/base/nsIDOMGlobalPropertyInitializer.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/interfaces/base/nsIDOMGlobalPropertyInitializer.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,19 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIDOMWindow.idl"
+
+[scriptable, uuid(6368a821-d3e2-4cbd-9699-5a8ba569e2f3)]
+interface nsIDOMGlobalPropertyInitializer : nsISupports
+{
+  /*
+   * Initialize the global property.
+   *
+   * @param window the global object on which the property is being retrieved.
+   *
+   * @returns a JS Object to use use as the property's value.
+   */
+  jsval init(in nsIDOMWindow window);
+};