diff -r 000000000000 -r 6474c204b198 xpcom/ds/nsProperties.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/ds/nsProperties.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,37 @@
+/* -*- 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 nsProperties_h___
+#define nsProperties_h___
+
+#include "nsIProperties.h"
+#include "nsInterfaceHashtable.h"
+#include "nsHashKeys.h"
+#include "nsAgg.h"
+#include "mozilla/Attributes.h"
+
+#define NS_PROPERTIES_CID                            \
+{ /* 4de2bc90-b1bf-11d3-93b6-00104ba0fd40 */         \
+    0x4de2bc90,                                      \
+    0xb1bf,                                          \
+    0x11d3,                                          \
+    {0x93, 0xb6, 0x00, 0x10, 0x4b, 0xa0, 0xfd, 0x40} \
+}
+
+typedef nsInterfaceHashtable<nsCharPtrHashKey, nsISupports>
+        nsProperties_HashBase;
+
+class nsProperties MOZ_FINAL : public nsIProperties,
+                               public nsProperties_HashBase {
+public:
+
+  NS_DECL_AGGREGATED
+  NS_DECL_NSIPROPERTIES
+
+  nsProperties(nsISupports *aOuter) { NS_INIT_AGGREGATED(aOuter); }
+  ~nsProperties() { }
+};
+
+#endif /* nsProperties_h___ */