Add rails to input wheel events.

Source/core/events/Event.h

 /*
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2001 Tobias Anton (anton@stud.fbi.fh-darmstadt.de)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 58 matching lines @@
         KEYDOWN             = 256,
         KEYUP               = 512,
         KEYPRESS            = 1024,
         DRAGDROP            = 2048,
         FOCUS               = 4096,
         BLUR                = 8192,
         SELECT              = 16384,
         CHANGE              = 32768
     };
 
+    enum RailsMode {
+        RailsModeFree       = 0,
+        RailsModeHorizontal = 1,
+        RailsModeVertical   = 2
+    };
+
     static PassRefPtrWillBeRawPtr<Event> create()
     {
         return adoptRefWillBeNoop(new Event);
     }
 
     // A factory for a simple event. The event doesn't bubble, and isn't
     // cancelable.
     // http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#fire-a-simple-event
     static PassRefPtrWillBeRawPtr<Event> create(const AtomicString& type)
     {
@@ skipping 130 matching lines @@
     OwnPtrWillBeMember<EventPath> m_eventPath;
     double m_uiCreateTime; // For input events, the time the event was recorded by the UI.
 };
 
 #define DEFINE_EVENT_TYPE_CASTS(typeName) \
     DEFINE_TYPE_CASTS(typeName, Event, event, event->is##typeName(), event.is##typeName())
 
 } // namespace blink
 
 #endif // Event_h