Disable rendering when suspending on chrome os

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 362 matching lines @@
     return window_cycle_controller_.get();
   }
   WindowSelectorController* window_selector_controller() {
     return window_selector_controller_.get();
   }
   FocusCycler* focus_cycler() { return focus_cycler_.get(); }
   DisplayController* display_controller() {
     return display_controller_.get();
   }
 #if defined(OS_CHROMEOS)
+  PowerEventObserver* power_event_observer() {
+    return power_event_observer_.get();
+  }
   TouchTransformerController* touch_transformer_controller() {
     return touch_transformer_controller_.get();
   }
 #endif  // defined(OS_CHROMEOS)
   MouseCursorEventFilter* mouse_cursor_filter() {
     return mouse_cursor_filter_.get();
   }
   EventTransformationHandler* event_transformation_handler() {
     return event_transformation_handler_.get();
   }
@@ skipping 363 matching lines @@
 
   // Injected content::GPUDataManager support.
   scoped_ptr<GPUSupport> gpu_support_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELL_H_