Implement cursor compositing mode on Ash

ash/shell.h

 // 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.
 
 #ifndef ASH_SHELL_H_
 #define ASH_SHELL_H_
 
 #include <utility>
 #include <vector>
 
@@ skipping 481 matching lines @@
   // TODO(oshima): Move these objects to DisplayController.
   chromeos::OutputConfigurator* output_configurator() {
     return output_configurator_.get();
   }
   internal::OutputConfiguratorAnimation* output_configurator_animation() {
     return output_configurator_animation_.get();
   }
   internal::DisplayErrorObserver* display_error_observer() {
     return display_error_observer_.get();
   }
+
+  // Toggles cursor compositing on/off. Native cursor is disabled when cursor
+  // compositing is enabled, and vice versa.
+  void SetCursorCompositingEnabled(bool enabled);
 #endif  // defined(USE_X11)
 
   internal::ResolutionNotificationController*
       resolution_notification_controller() {
     return resolution_notification_controller_.get();
   }
 #endif  // defined(OS_CHROMEOS)
 
   WindowTreeHostFactory* root_window_host_factory() {
     return root_window_host_factory_.get();
@@ skipping 203 matching lines @@
 
   // Injected content::GPUDataManager support.
   scoped_ptr<GPUSupport> gpu_support_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELL_H_