diff -r 000000000000 -r 6474c204b198 dom/events/DataContainerEvent.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/events/DataContainerEvent.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,59 @@
+/* -*- 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 mozilla_dom_DataContainerEvent_h_
+#define mozilla_dom_DataContainerEvent_h_
+
+#include "mozilla/dom/DataContainerEventBinding.h"
+#include "mozilla/dom/Event.h"
+#include "nsIDOMDataContainerEvent.h"
+#include "nsInterfaceHashtable.h"
+
+namespace mozilla {
+namespace dom {
+
+class DataContainerEvent : public Event,
+                           public nsIDOMDataContainerEvent
+{
+public:
+  DataContainerEvent(EventTarget* aOwner,
+                     nsPresContext* aPresContext,
+                     WidgetEvent* aEvent);
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(DataContainerEvent, Event)
+
+  NS_FORWARD_TO_EVENT
+
+  NS_DECL_NSIDOMDATACONTAINEREVENT
+
+  virtual JSObject*
+  WrapObject(JSContext* aCx) MOZ_OVERRIDE
+  {
+    return DataContainerEventBinding::Wrap(aCx, this);
+  }
+
+  already_AddRefed<nsIVariant> GetData(const nsAString& aKey)
+  {
+    nsCOMPtr<nsIVariant> val;
+    GetData(aKey, getter_AddRefs(val));
+    return val.forget();
+  }
+
+  void SetData(JSContext* aCx, const nsAString& aKey,
+               JS::Handle<JS::Value> aVal, ErrorResult& aRv);
+
+private:
+  static PLDHashOperator
+    TraverseEntry(const nsAString& aKey, nsIVariant* aDataItem, void* aUserArg);
+
+  nsInterfaceHashtable<nsStringHashKey, nsIVariant> mData;
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_DataContainerEvent_h_