Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/extensions/component_loader.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/extensions/component_loader.h"
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/json/json_string_value_serializer.h"
 #include "base/path_service.h"
@@ skipping 389 matching lines @@
   // the browser process has started.
   AddOrReloadEnterpriseWebStore();
 
 #if defined(USE_ASH)
   AddChromeApp();
 #endif
 
   AddScriptBubble();
 }
 
-void ComponentLoader::Observe(
-    int type,
-    const content::NotificationSource& source,
-    const content::NotificationDetails& details) {
-  if (type == chrome::NOTIFICATION_PREF_CHANGED) {
-    const std::string* name =
-        content::Details<const std::string>(details).ptr();
-    if (*name == prefs::kEnterpriseWebStoreURL)
-      AddOrReloadEnterpriseWebStore();
-    else
-      NOTREACHED();
-  } else {
+void ComponentLoader::OnPreferenceChanged(PrefServiceBase* service,
+                                          const std::string& pref_name) {
+  if (pref_name == prefs::kEnterpriseWebStoreURL)
+    AddOrReloadEnterpriseWebStore();
+  else
     NOTREACHED();
-  }
 }
 
 // static
 void ComponentLoader::RegisterUserPrefs(PrefService* prefs) {
   prefs->RegisterStringPref(prefs::kEnterpriseWebStoreURL,
                             std::string() /* default_value */,
                             PrefService::UNSYNCABLE_PREF);
   prefs->RegisterStringPref(prefs::kEnterpriseWebStoreName,
                             std::string() /* default_value */,
                             PrefService::UNSYNCABLE_PREF);
 }
 
 }  // namespace extensions