diff -r 000000000000 -r 6474c204b198 dom/events/TransitionEvent.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/events/TransitionEvent.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,51 @@
+/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
+/* 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_TransitionEvent_h_
+#define mozilla_dom_TransitionEvent_h_
+
+#include "mozilla/EventForwards.h"
+#include "mozilla/dom/Event.h"
+#include "mozilla/dom/TransitionEventBinding.h"
+#include "nsIDOMTransitionEvent.h"
+
+class nsAString;
+
+namespace mozilla {
+namespace dom {
+
+class TransitionEvent : public Event,
+                        public nsIDOMTransitionEvent
+{
+public:
+  TransitionEvent(EventTarget* aOwner,
+                  nsPresContext* aPresContext,
+                  InternalTransitionEvent* aEvent);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_FORWARD_TO_EVENT
+  NS_DECL_NSIDOMTRANSITIONEVENT
+
+  static already_AddRefed<TransitionEvent>
+  Constructor(const GlobalObject& aGlobal,
+              const nsAString& aType,
+              const TransitionEventInit& aParam,
+              ErrorResult& aRv);
+
+  virtual JSObject* WrapObject(JSContext* aCx) MOZ_OVERRIDE
+  {
+    return TransitionEventBinding::Wrap(aCx, this);
+  }
+
+  // xpidl implementation
+  // GetPropertyName(nsAString& aPropertyName)
+  // GetPseudoElement(nsAString& aPreudoElement)
+
+  float ElapsedTime();
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_TransitionEvent_h_