diff -r 000000000000 -r 6474c204b198 content/xul/templates/src/nsContentSupportMap.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/xul/templates/src/nsContentSupportMap.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,38 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "nsContentSupportMap.h"
+#include "nsXULElement.h"
+
+void
+nsContentSupportMap::Init()
+{
+    PL_DHashTableInit(&mMap, PL_DHashGetStubOps(), nullptr,
+                      sizeof(Entry), PL_DHASH_MIN_SIZE);
+}
+
+void
+nsContentSupportMap::Finish()
+{
+    if (mMap.ops)
+        PL_DHashTableFinish(&mMap);
+}
+
+nsresult
+nsContentSupportMap::Remove(nsIContent* aElement)
+{
+    if (!mMap.ops)
+        return NS_ERROR_NOT_INITIALIZED;
+
+    nsIContent* child = aElement;    
+    do {
+        PL_DHashTableOperate(&mMap, child, PL_DHASH_REMOVE);
+        child = child->GetNextNode(aElement);
+    } while(child);
+
+    return NS_OK;
+}
+
+