Eliminate NOTIFICATION_HISTORY_LOADED notification

chrome/browser/ui/cocoa/history_menu_bridge.h

 // Copyright (c) 2011 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_COCOA_HISTORY_MENU_BRIDGE_H_
 #define CHROME_BROWSER_UI_COCOA_HISTORY_MENU_BRIDGE_H_
 
 #import <Cocoa/Cocoa.h>
 #include <map>
 #include <vector>
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/memory/ref_counted.h"
+#include "base/scoped_observer.h"
 #include "base/task/cancelable_task_tracker.h"
 #import "chrome/browser/favicon/favicon_service.h"
 #include "chrome/browser/history/history_service.h"
 #include "chrome/browser/sessions/tab_restore_service.h"
 #include "chrome/browser/sessions/tab_restore_service_observer.h"
 #import "chrome/browser/ui/cocoa/main_menu_item.h"
 #include "components/history/core/browser/history_service_observer.h"
 #include "components/sessions/session_id.h"
 #include "content/public/browser/notification_observer.h"
 
@@ skipping 118 matching lines @@
   void BuildMenu() override;
 
   // history::HistoryServiceObserver:
   void OnURLVisited(HistoryService* history_service,
                     ui::PageTransition transition,
                     const history::URLRow& row,
                     const history::RedirectList& redirects,
                     base::Time visit_time) override;
   void OnURLsModified(HistoryService* history_service,
                       const history::URLRows& changed_urls) override;
+  void OnHistoryServiceLoaded(HistoryService* service) override;
 
   // Looks up an NSMenuItem in the |menu_item_map_| and returns the
   // corresponding HistoryItem.
   HistoryItem* HistoryItemForMenuItem(NSMenuItem* item);
 
   // I wish I has a "friend @class" construct. These are used by the HMCC
   // to access model information when responding to actions.
   HistoryService* service();
   Profile* profile();
 
@@ skipping 71 matching lines @@
   // Requests to re-create the menu are coalesced. |create_in_progress_| is true
   // when either waiting for the history service to return query results, or
   // when the menu is rebuilding. |need_recreate_| is true whenever a rebuild
   // has been scheduled but is waiting for the current one to finish.
   bool create_in_progress_;
   bool need_recreate_;
 
   // The default favicon if a HistoryItem does not have one.
   base::scoped_nsobject<NSImage> default_favicon_;
 
+  ScopedObserver<HistoryService, HistoryServiceObserver>
+      history_service_observer_;
+
   DISALLOW_COPY_AND_ASSIGN(HistoryMenuBridge);
 };
 
 #endif  // CHROME_BROWSER_UI_COCOA_HISTORY_MENU_BRIDGE_H_