aura: Remove event-dispatch methods from WindowTreeHostDelegate interface.

ui/aura/root_window_host_win.h

Index: ui/aura/root_window_host_win.h
diff --git a/ui/aura/root_window_host_win.h b/ui/aura/root_window_host_win.h
index 2806431a20caa441cdfb5b51cb5756941d32e2e2..96f3e358103301a42febf86f0daa5e52848d7272 100644
--- a/ui/aura/root_window_host_win.h
+++ b/ui/aura/root_window_host_win.h
@@ -8,11 +8,14 @@
 #include "base/compiler_specific.h"
 #include "ui/aura/aura_export.h"
 #include "ui/aura/window_tree_host.h"
+#include "ui/events/event_source.h"
 #include "ui/gfx/win/window_impl.h"
 
 namespace aura {
 
-class WindowTreeHostWin : public WindowTreeHost, public gfx::WindowImpl {
+class WindowTreeHostWin : public WindowTreeHost,
+                          public ui::EventSource,
+                          public gfx::WindowImpl {
  public:
   WindowTreeHostWin(const gfx::Rect& bounds);
   virtual ~WindowTreeHostWin();
@@ -39,6 +42,9 @@ class WindowTreeHostWin : public WindowTreeHost, public gfx::WindowImpl {
   virtual void OnDeviceScaleFactorChanged(float device_scale_factor) OVERRIDE;
   virtual void PrepareForShutdown() OVERRIDE;
 
+  // ui::EventSource:
+  virtual ui::EventProcessor* GetEventProcessor() OVERRIDE;
+
  private:
   CR_BEGIN_MSG_MAP_EX(WindowTreeHostWin)
     // Range handlers must go first!