Add Aura support to views:

views/native_types.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef VIEWS_NATIVE_TYPES_H_
 #define VIEWS_NATIVE_TYPES_H_
 #pragma once
 
 #include "ui/gfx/native_widget_types.h"
 
 #if defined(OS_LINUX)
 typedef union _GdkEvent GdkEvent;
 #endif
 #if defined(USE_X11)
 typedef union _XEvent XEvent;
 #endif
 
+#if defined(USE_AURA)
+namespace aura {
+class Event;
+}
+#endif
+
 namespace views {
 
 // A note about NativeEvent and NativeEvent2.
 // 1. Eventually TOOLKIT_VIEWS will converge on using XEvent as we remove
 //    Gtk/Gdk from the stack.
 // 2. TOUCH_UI needs XEvents now for certain event types.
 // 3. TOUCH_UI also needs GdkEvents for certain event types.
 //
 //    => NativeEvent and NativeEvent2.
 //
 // Once we replace usage of Gtk/Gdk types with Xlib types across the board in
 // views, we can remove NativeEvent2 and typedef XEvent* to NativeEvent. The
 // world will then be beautiful(ish).
 
-#if defined(OS_WIN)
+#if defined(USE_AURA)
+typedef aura::Event* NativeEvent;
+#elif defined(OS_WIN)
 typedef MSG NativeEvent;
-#endif
-#if defined(OS_LINUX)
+#elif defined(OS_LINUX)
 typedef GdkEvent* NativeEvent;
 #endif
+
 #if defined(USE_X11)
 typedef XEvent* NativeEvent2;
 #else
 typedef void* NativeEvent2;
 #endif
 
 }  // namespace views
 
 #endif  // VIEWS_NATIVE_TYPES_H_