Save display preference when all display configuration changes has been completed.

chrome/browser/chromeos/display/display_configuration_observer.cc

+// Copyright (c) 2013 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 "chrome/browser/chromeos/display/display_configuration_observer.h"
+
+#include "ash/display/display_controller.h"
+#include "ash/shell.h"
+#include "chrome/browser/chromeos/display/display_preferences.h"
+
+namespace chromeos {
+
+DisplayConfigurationObserver::DisplayConfigurationObserver() {
+  ash::Shell::GetInstance()->display_controller()->AddObserver(this);
+}
+
+DisplayConfigurationObserver::~DisplayConfigurationObserver() {
+  ash::Shell::GetInstance()->display_controller()->RemoveObserver(this);
+}
+
+void DisplayConfigurationObserver::OnDisplayConfigurationChanging() {
+}
+
+void DisplayConfigurationObserver::OnDisplayConfigurationChanged() {
+  StoreDisplayPrefs();
+}
+
+}  // namespace chromeos