Add KeepAliveStateObserver, add the Restart option

chrome/browser/background/background_mode_manager.cc

 // 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.
 
 #include "chrome/browser/background/background_mode_manager.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <string>
 #include <utility>
@@ skipping 68 matching lines @@
 // previously logged data. When making changes, also update histograms.xml.
 enum MenuItem {
   MENU_ITEM_ABOUT = 0,
   MENU_ITEM_TASK_MANAGER = 1,
   MENU_ITEM_BACKGROUND_CLIENT = 2,
   MENU_ITEM_KEEP_RUNNING = 3,
   MENU_ITEM_EXIT = 4,
   MENU_ITEM_NUM_STATES
 };
 
-const KeepAliveOptions kKeepAliveOptions = {"Background"};
+const KeepAliveOptions kKeepAliveOptions = {"Background",
+                                            KeepAliveOptionRestart::ENABLED};
 
 void RecordMenuItemClick(MenuItem item) {
   UMA_HISTOGRAM_ENUMERATION("BackgroundMode.MenuItemClick", item,
                             MENU_ITEM_NUM_STATES);
 }
 }  // namespace
 
 BackgroundModeManager::BackgroundModeData::BackgroundModeData(
     Profile* profile,
     CommandIdHandlerVector* command_id_handler_vector)
@@ skipping 926 matching lines @@
     }
   }
   return profile_it;
 }
 
 bool BackgroundModeManager::IsBackgroundModePrefEnabled() const {
   PrefService* service = g_browser_process->local_state();
   DCHECK(service);
   return service->GetBoolean(prefs::kBackgroundModeEnabled);
 }