diff -r 000000000000 -r 6474c204b198 dom/base/nsIJSNativeInitializer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/base/nsIJSNativeInitializer.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; 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/. */
+
+#ifndef nsIJSNativeInitializer_h__
+#define nsIJSNativeInitializer_h__
+
+#include "nsISupports.h"
+
+#define NS_IJSNATIVEINITIALIZER_IID \
+{ 0xdb48eee5, 0x89a4, 0x4f18,       \
+  { 0x86, 0xd0, 0x4c, 0x4e, 0x9d, 0x4b, 0xf8, 0x7e } }
+
+
+/**
+ * A JavaScript specific interface used to initialize new
+ * native objects, created as a result of calling a
+ * JavaScript constructor. The arguments are passed in
+ * their raw form as JS::Value's.
+ */
+
+class nsIJSNativeInitializer : public nsISupports {
+public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_IJSNATIVEINITIALIZER_IID)
+
+  /**
+   * Initialize a newly created native instance using the owner of the
+   * constructor and the parameters passed into the JavaScript constructor.
+   */
+  NS_IMETHOD Initialize(nsISupports* aOwner, JSContext *cx, JSObject *obj,
+                        const JS::CallArgs& args) = 0;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsIJSNativeInitializer,
+                              NS_IJSNATIVEINITIALIZER_IID)
+
+#endif // nsIJSNativeInitializer_h__