Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/extensions/extension_service.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_
 
 #include <list>
 #include <map>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/prefs/public/pref_change_registrar.h"
+#include "base/prefs/public/pref_observer.h"
 #include "base/string16.h"
 #include "chrome/browser/extensions/app_shortcut_manager.h"
 #include "chrome/browser/extensions/app_sync_bundle.h"
 #include "chrome/browser/extensions/extension_icon_manager.h"
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_sync_bundle.h"
 #include "chrome/browser/extensions/extension_toolbar_model.h"
 #include "chrome/browser/extensions/extension_warning_set.h"
 #include "chrome/browser/extensions/extensions_quota_service.h"
@@ skipping 103 matching lines @@
   virtual void SyncExtensionChangeIfNeeded(
       const extensions::Extension& extension) = 0;
 
   virtual bool is_ready() = 0;
 };
 
 // Manages installed and running Chromium extensions.
 class ExtensionService
     : public ExtensionServiceInterface,
       public extensions::ExternalProviderInterface::VisitorInterface,
-      public content::NotificationObserver {
+      public content::NotificationObserver,
+      public PrefObserver {
  public:
   // The name of the directory inside the profile where extensions are
   // installed to.
   static const char kInstallDirectoryName[];
 
   // If auto-updates are turned on, default to running every 5 hours.
   static const int kDefaultUpdateFrequencySeconds = 60 * 60 * 5;
 
   // The name of the directory inside the profile where per-app local settings
   // are stored.
@@ skipping 460 matching lines @@
 
   // Marks alertable extensions as acknowledged, after the user presses the
   // accept button.
   void HandleExtensionAlertAccept();
 
   // content::NotificationObserver
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
+  // PrefObserver
+  virtual void OnPreferenceChanged(PrefServiceBase* service,
+                                   const std::string& pref_name) OVERRIDE;
+
   // Whether there are any apps installed. Component apps are not included.
   bool HasApps() const;
 
   // Gets the set of loaded app ids. Component apps are not included.
   extensions::ExtensionIdSet GetAppIds() const;
 
   // Record a histogram using the PermissionMessage enum values for each
   // permission in |e|.
   // NOTE: If this is ever called with high frequency, the implementation may
   // need to be made more efficient.
@@ skipping 312 matching lines @@
 #endif
 
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsWithUnlimtedStorage);
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsAndCheckStorageProtection);
   DISALLOW_COPY_AND_ASSIGN(ExtensionService);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_