Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/policy/url_blacklist_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/policy/url_blacklist_manager.h"
 
 #include "base/bind.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
 #include "base/string_number_conversions.h"
@@ skipping 279 matching lines @@
 void URLBlacklistManager::ShutdownOnUIThread() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   // Cancel any pending updates, and stop listening for pref change updates.
   ui_weak_ptr_factory_.InvalidateWeakPtrs();
   pref_change_registrar_.RemoveAll();
 }
 
 URLBlacklistManager::~URLBlacklistManager() {
 }
 
-void URLBlacklistManager::Observe(int type,
-                                  const content::NotificationSource& source,
-                                  const content::NotificationDetails& details) {
+void URLBlacklistManager::OnPreferenceChanged(PrefServiceBase* prefs,
+                                              const std::string& pref_name) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK(type == chrome::NOTIFICATION_PREF_CHANGED);
-  PrefService* prefs = content::Source<PrefService>(source).ptr();
   DCHECK(prefs == pref_service_);
-  std::string* pref_name = content::Details<std::string>(details).ptr();
-  DCHECK(*pref_name == prefs::kUrlBlacklist ||
-         *pref_name == prefs::kUrlWhitelist);
+  DCHECK(pref_name == prefs::kUrlBlacklist ||
+         pref_name == prefs::kUrlWhitelist);
   ScheduleUpdate();
 }
 
 void URLBlacklistManager::ScheduleUpdate() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   // Cancel pending updates, if any. This can happen if two preferences that
   // change the blacklist are updated in one message loop cycle. In those cases,
   // only rebuild the blacklist after all the preference updates are processed.
   ui_weak_ptr_factory_.InvalidateWeakPtrs();
   MessageLoop::current()->PostTask(
@@ skipping 47 matching lines @@
 
 // static
 void URLBlacklistManager::RegisterPrefs(PrefService* pref_service) {
   pref_service->RegisterListPref(prefs::kUrlBlacklist,
                                  PrefService::UNSYNCABLE_PREF);
   pref_service->RegisterListPref(prefs::kUrlWhitelist,
                                  PrefService::UNSYNCABLE_PREF);
 }
 
 }  // namespace policy