diff -r 000000000000 -r 6474c204b198 dom/events/WheelEvent.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/events/WheelEvent.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,60 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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_WheelEvent_h_
+#define mozilla_dom_WheelEvent_h_
+
+#include "nsIDOMWheelEvent.h"
+#include "mozilla/dom/MouseEvent.h"
+#include "mozilla/dom/WheelEventBinding.h"
+#include "mozilla/EventForwards.h"
+
+namespace mozilla {
+namespace dom {
+
+class WheelEvent : public MouseEvent,
+                   public nsIDOMWheelEvent
+{
+public:
+  WheelEvent(EventTarget* aOwner,
+             nsPresContext* aPresContext,
+             WidgetWheelEvent* aWheelEvent);
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  // nsIDOMWheelEvent Interface
+  NS_DECL_NSIDOMWHEELEVENT
+  
+  // Forward to base class
+  NS_FORWARD_TO_MOUSEEVENT
+
+  static
+  already_AddRefed<WheelEvent> Constructor(const GlobalObject& aGlobal,
+                                           const nsAString& aType,
+                                           const WheelEventInit& aParam,
+                                           ErrorResult& aRv);
+
+  virtual JSObject* WrapObject(JSContext* aCx) MOZ_OVERRIDE
+  {
+    return WheelEventBinding::Wrap(aCx, this);
+  }
+
+  // NOTE: DeltaX(), DeltaY() and DeltaZ() return CSS pixels when deltaMode is
+  //       DOM_DELTA_PIXEL. (The internal event's delta values are device pixels
+  //       if it's dispatched by widget)
+  double DeltaX();
+  double DeltaY();
+  double DeltaZ();
+  uint32_t DeltaMode();
+
+private:
+  int32_t mAppUnitsPerDevPixel;
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_WheelEvent_h_