Consolidate win/x dispatchers

ui/aura/dispatcher_win.cc

Index: ui/aura/dispatcher_win.cc
diff --git a/ui/aura/dispatcher_win.cc b/ui/aura/dispatcher_win.cc
index 9f604363bd4eb7fcf7b32d3cfb5c1eeff1ffbe01..c406edee8582346f2bc6e7d28aee8cc59c409f54 100644
--- a/ui/aura/dispatcher_win.cc
+++ b/ui/aura/dispatcher_win.cc
@@ -14,13 +14,13 @@ class DispatcherWin : public MessageLoop::Dispatcher {
   virtual ~DispatcherWin() {}
 
   // Overridden from MessageLoop::Dispatcher:
-  virtual bool Dispatch(const MSG& msg) OVERRIDE;
+  virtual bool Dispatch(const base::NativeEvent& event) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DispatcherWin);
 };
 
-bool DispatcherWin::Dispatch(const MSG& msg) {
+bool DispatcherWin::Dispatch(const base::NativeEvent& msg) {
   TranslateMessage(&msg);
   DispatchMessage(&msg);
   return true;