Wiring metro mouse events to aura viewer

ui/aura/root_window_host.h

Index: ui/aura/root_window_host.h
===================================================================
--- ui/aura/root_window_host.h	(revision 160403)
+++ ui/aura/root_window_host.h	(working copy)
@@ -31,13 +31,15 @@
   virtual ~RootWindowHost() {}
 
   // Creates a new RootWindowHost. The caller owns the returned value.
-  static RootWindowHost* Create(RootWindowHostDelegate* delegate,
-                                const gfx::Rect& bounds);
+  static RootWindowHost* Create(const gfx::Rect& bounds);
 
   // Returns the actual size of the screen.
   // (gfx::Screen only reports on the virtual desktop exposed by Aura.)
   static gfx::Size GetNativeScreenSize();
 
+  // Sets the delegate, which is normally done by the root window.
+  virtual void SetDelegate(RootWindowHostDelegate* delegate) = 0;
+
   virtual RootWindow* GetRootWindow() = 0;
 
   // Returns the RootWindowHost for the specified accelerated widget, or NULL if