Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/ui/webui/options/core_options_handler.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/ui/webui/options/core_options_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/json/json_reader.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 117 matching lines @@
   for (PreferenceCallbackMap::const_iterator iter = pref_callback_map_.begin();
        iter != pref_callback_map_.end();
        ++iter) {
     if (last_pref != iter->first) {
       StopObservingPref(iter->first);
       last_pref = iter->first;
     }
   }
 }
 
-void CoreOptionsHandler::Observe(int type,
-                                 const content::NotificationSource& source,
-                                 const content::NotificationDetails& details) {
-  if (type == chrome::NOTIFICATION_PREF_CHANGED) {
-    std::string* pref_name = content::Details<std::string>(details).ptr();
-    if (*pref_name == prefs::kClearPluginLSODataEnabled) {
-      // This preference is stored in Local State, not in the user preferences.
-      UpdateClearPluginLSOData();
-      return;
-    }
-    if (*pref_name == prefs::kPepperFlashSettingsEnabled) {
-      UpdatePepperFlashSettingsEnabled();
-      return;
-    }
-    NotifyPrefChanged(*pref_name, std::string());
+void CoreOptionsHandler::OnPreferenceChanged(PrefServiceBase* service,
+                                             const std::string& pref_name) {
+  if (pref_name == prefs::kClearPluginLSODataEnabled) {
+    // This preference is stored in Local State, not in the user preferences.
+    UpdateClearPluginLSOData();
+    return;
   }
+  if (pref_name == prefs::kPepperFlashSettingsEnabled) {
+    UpdatePepperFlashSettingsEnabled();
+    return;
+  }
+  NotifyPrefChanged(pref_name, std::string());
 }
 
 void CoreOptionsHandler::RegisterMessages() {
   registrar_.Init(Profile::FromWebUI(web_ui())->GetPrefs());
   local_state_registrar_.Init(g_browser_process->local_state());
 
   web_ui()->RegisterMessageCallback("coreOptionsInitialize",
       base::Bind(&CoreOptionsHandler::HandleInitialize,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("fetchPrefs",
@@ skipping 371 matching lines @@
 
 void CoreOptionsHandler::UpdatePepperFlashSettingsEnabled() {
   scoped_ptr<base::Value> enabled(
       base::Value::CreateBooleanValue(
           plugin_status_pref_setter_.IsPepperFlashSettingsEnabled()));
   web_ui()->CallJavascriptFunction(
       "OptionsPage.setPepperFlashSettingsEnabled", *enabled);
 }
 
 }  // namespace options