chromeos: Turn off displays on suspend

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

 // 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.
 
 #include "ui/ozone/platform/drm/host/drm_display_host_manager.h"
 
 #include <fcntl.h>
 #include <stddef.h>
 #include <xf86drm.h>
 
@@ skipping 202 matching lines @@
     return;
   }
 
   relinquish_display_control_callback_ = callback;
   display_control_change_pending_ = true;
 
   if (!proxy_->GpuRelinquishDisplayControl())
     GpuRelinquishedDisplayControl(false);
 }
 
+void DrmDisplayHostManager::GetCachedDisplays(
+    const GetDisplaysCallback& callback) {
+  RunUpdateDisplaysCallback(callback);
+}
+
 void DrmDisplayHostManager::UpdateDisplays(
     const GetDisplaysCallback& callback) {
   get_displays_callback_ = callback;
   if (!proxy_->GpuRefreshNativeDisplays()) {
     get_displays_callback_.Reset();
     RunUpdateDisplaysCallback(callback);
   }
 }
 
 void DrmDisplayHostManager::OnDeviceEvent(const DeviceEvent& event) {
@@ skipping 225 matching lines @@
 
   callback.Run(snapshots);
 }
 
 void DrmDisplayHostManager::NotifyDisplayDelegate() const {
   if (delegate_)
     delegate_->OnConfigurationChanged();
 }
 
 }  // namespace ui