Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/ui/webui/ntp/new_tab_ui.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 "build/build_config.h"
 
 #include "chrome/browser/ui/webui/ntp/new_tab_ui.h"
 
 #include <set>
 
@@ skipping 231 matching lines @@
 }
 
 void NewTabUI::RenderViewReused(RenderViewHost* render_view_host) {
   StartTimingPaint(render_view_host);
 }
 
 void NewTabUI::Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) {
   switch (type) {
-    case chrome::NOTIFICATION_PREF_CHANGED: {  // kShowBookmarkBar
-      StringValue attached(
-          GetProfile()->GetPrefs()->GetBoolean(prefs::kShowBookmarkBar) ?
-              "true" : "false");
-      web_ui()->CallJavascriptFunction("ntp.setBookmarkBarAttached", attached);
-      break;
-    }
 #if defined(ENABLE_THEMES)
     case chrome::NOTIFICATION_BROWSER_THEME_CHANGED: {
       InitializeCSSCaches();
       StringValue attribution(
           ThemeServiceFactory::GetForProfile(GetProfile())->HasCustomImage(
               IDR_THEME_NTP_ATTRIBUTION) ? "true" : "false");
       web_ui()->CallJavascriptFunction("ntp.themeChanged", attribution);
       break;
     }
     case chrome::NOTIFICATION_NTP_BACKGROUND_THEME_Y_POS_CHANGED: {
@@ skipping 12 matching lines @@
 #endif
     case content::NOTIFICATION_RENDER_WIDGET_HOST_DID_UPDATE_BACKING_STORE: {
       last_paint_ = base::TimeTicks::Now();
       break;
     }
     default:
       CHECK(false) << "Unexpected notification: " << type;
   }
 }
 
+void NewTabUI::OnPreferenceChanged(PrefServiceBase* service,
+                                   const std::string& pref_name) {
+  StringValue attached(
+      GetProfile()->GetPrefs()->GetBoolean(prefs::kShowBookmarkBar) ?
+          "true" : "false");
+  web_ui()->CallJavascriptFunction("ntp.setBookmarkBarAttached", attached);
+}
+
 void NewTabUI::InitializeCSSCaches() {
 #if defined(ENABLE_THEMES)
   Profile* profile = GetProfile();
   ThemeSource* theme = new ThemeSource(profile);
   ChromeURLDataManager::AddDataSource(profile, theme);
 #endif
 }
 
 // static
 void NewTabUI::RegisterUserPrefs(PrefService* prefs) {
@@ skipping 134 matching lines @@
 void NewTabUI::NewTabHTMLSource::AddResource(const char* resource,
                                              const char* mime_type,
                                              int resource_id) {
   DCHECK(resource);
   DCHECK(mime_type);
   resource_map_[std::string(resource)] =
       std::make_pair(std::string(mime_type), resource_id);
 }
 
 NewTabUI::NewTabHTMLSource::~NewTabHTMLSource() {}