chromeos: Turn off displays on suspend

ui/ozone/platform/drm/host/drm_display_host_manager.h

 // Copyright 2014 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 UI_OZONE_PLATFORM_DRM_HOST_DRM_DISPLAY_HOST_MANAGER_H_
 #define UI_OZONE_PLATFORM_DRM_HOST_DRM_DISPLAY_HOST_MANAGER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 33 matching lines @@
                         InputControllerEvdev* input_controller);
   ~DrmDisplayHostManager() override;
 
   DrmDisplayHost* GetDisplay(int64_t display_id);
 
   // External API.
   void AddDelegate(DrmNativeDisplayDelegate* delegate);
   void RemoveDelegate(DrmNativeDisplayDelegate* delegate);
   void TakeDisplayControl(const DisplayControlCallback& callback);
   void RelinquishDisplayControl(const DisplayControlCallback& callback);
+  void GetCachedDisplays(const GetDisplaysCallback& callback);
   void UpdateDisplays(const GetDisplaysCallback& callback);
 
   // DeviceEventObserver overrides:
   void OnDeviceEvent(const DeviceEvent& event) override;
 
   // GpuThreadObserver overrides:
   void OnGpuThreadReady() override;
   void OnGpuThreadRetired() override;
 
   // Communication-free implementations of actions performed in response to
@@ skipping 73 matching lines @@
   std::unique_ptr<DrmDeviceHandle> primary_drm_device_handle_;
 
   base::WeakPtrFactory<DrmDisplayHostManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DrmDisplayHostManager);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRM_HOST_DRM_DISPLAY_HOST_MANAGER_H_