Adding GetEventSource() method to the WindowTreeHost class.

ui/aura/remote_window_tree_host_win.cc

 // Copyright (c) 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.
 
 #include "ui/aura/remote_window_tree_host_win.h"
 
 #include <windows.h>
 
 #include <algorithm>
 
@@ skipping 355 matching lines @@
 }
 
 bool RemoteWindowTreeHostWin::IsForegroundWindow() {
   return ::GetForegroundWindow() == remote_window_;
 }
 
 Window* RemoteWindowTreeHostWin::GetAshWindow() {
   return window();
 }
 
+ui::EventSource* RemoteWindowTreeHostWin::GetEventSource() {
+  return this;
+}
+
 gfx::AcceleratedWidget RemoteWindowTreeHostWin::GetAcceleratedWidget() {
   if (remote_window_)
     return remote_window_;
   // Getting here should only happen for ash_unittests.exe and related code.
   return ::GetDesktopWindow();
 }
 
 void RemoteWindowTreeHostWin::Show() {
   ui::RemoteInputMethodPrivateWin* remote_input_method_private =
       GetRemoteInputMethodPrivate();
@@ skipping 363 matching lines @@
 }
 
 void RemoteWindowTreeHostWin::SetEventFlags(uint32 flags) {
   if (flags == event_flags_)
     return;
   event_flags_ = flags;
   SetVirtualKeyStates(event_flags_);
 }
 
 }  // namespace aura