diff -r 000000000000 -r 6474c204b198 dom/interfaces/base/nsIDOMConstructor.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/interfaces/base/nsIDOMConstructor.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 sw=2 et tw=80: */
+/* 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 "domstubs.idl"
+
+[scriptable, uuid(0ccbcf19-d1b4-489e-984c-cd8c43672bb9)]
+interface nsIDOMDOMConstructor : nsISupports
+{
+  AString toString();
+};
+