Wiring metro mouse events to aura viewer

ui/metro_viewer/metro_viewer_messages.h

 // Copyright 2012 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.
 
 // Multiply-included message file, no include guard.
 
 #include "base/basictypes.h"
 #include "ipc/ipc_message_macros.h"
 #include "ui/gfx/native_widget_types.h"
 
 #define IPC_MESSAGE_START MetroViewerMsgStart
 
 // Messages sent from the viewer to the browser.
 
 // Inform the browser of the surface to target for compositing.
 IPC_MESSAGE_CONTROL1(MetroViewerHostMsg_SetTargetSurface,
                      gfx::NativeViewId /* target hwnd */)
+// Informs the browser that the mouse moved.
+IPC_MESSAGE_CONTROL3(MetroViewerHostMsg_MouseMoved,
+                     int,       /* x-coordinate */
+                     int,       /* y-coordinate */
+                     int        /* modifiers */)
+// Inforoms the brower that a mouse button was pressed.
+IPC_MESSAGE_CONTROL3(MetroViewerHostMsg_MouseButton,
+                     int,       /* x-coordinate */
+                     int,       /* y-coordinate */
+                     int        /* modifiers */)
 
-IPC_MESSAGE_CONTROL3(MetroViewerHostMsg_MouseEvent,
-                     int,       /* msg */
-                     uintptr_t, /* message's wParam */
-                     intptr_t   /* message's lParam */)
+