Add device policy to disallow shutdown - ash UI modifications

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 227 matching lines @@
 
   void SetNativeWindowDelegate(NativeWindowDelegate* native_window_delegate);
 
   // NetworkStateInformer::NetworkStateInformerObserver implementation:
   virtual void OnNetworkReady() override;
   virtual void UpdateState(ErrorScreenActor::ErrorReason reason) override;
 
   // Required Local State preferences.
   static void RegisterPrefs(PrefRegistrySimple* registry);
 
+  // Checks whether the device policy allows the system to be shut down and if
+  // so initiates the shutdown. If system shutdown is forbidden this function
+  // triggers a reboot.
+  static void RequestShutdown();
+
   // OobeUI::Observer implemetation.
   virtual void OnCurrentScreenChanged(OobeUI::Screen current_screen,
                                       OobeUI::Screen new_screen) override;
 
   // Returns least used user login input method.
   std::string GetUserLRUInputMethod(const std::string& username) const;
 
   void SetFocusPODCallbackForTesting(base::Closure callback);
 
  private:
@@ skipping 88 matching lines @@
   void HandleGetUsers();
   void HandleAuthenticateUser(const std::string& username,
                               const std::string& password);
   void HandleAttemptUnlock(const std::string& username);
   void HandleLaunchDemoUser();
   void HandleLaunchIncognito();
   void HandleLaunchPublicSession(const std::string& user_id,
                                  const std::string& locale,
                                  const std::string& input_method);
   void HandleOfflineLogin(const base::ListValue* args);
+  void HandleRestartSystem();
   void HandleShutdownSystem();
   void HandleLoadWallpaper(const std::string& email);
   void HandleRebootSystem();
   void HandleRemoveUser(const std::string& email);
   void HandleShowAddUser(const base::ListValue* args);
   void HandleToggleEnrollmentScreen();
   void HandleToggleEnableDebuggingScreen();
   void HandleToggleKioskEnableScreen();
   void HandleToggleResetScreen();
   void HandleToggleKioskAutolaunchScreen();
@@ skipping 148 matching lines @@
   scoped_ptr<ErrorScreensHistogramHelper> histogram_helper_;
 
   base::WeakPtrFactory<SigninScreenHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SigninScreenHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_