Use PrefChangeRegistrar everywhere

chrome/browser/translate/translate_manager.cc

Index: chrome/browser/translate/translate_manager.cc
diff --git a/chrome/browser/translate/translate_manager.cc b/chrome/browser/translate/translate_manager.cc
index 6f649fd2f78e56ebd8253e71ef26e24fb72754dd..1c70dd4416963be21f44cc91d750b9c422bd4af3 100644
--- a/chrome/browser/translate/translate_manager.cc
+++ b/chrome/browser/translate/translate_manager.cc
@@ -249,7 +249,7 @@ void TranslateManager::Observe(NotificationType type,
       // We should know about this profile since we are listening for
       // notifications on it.
       DCHECK(count > 0);
-      profile->GetPrefs()->RemovePrefObserver(prefs::kAcceptLanguages, this);
+      pref_change_registrar_.Remove(prefs::kAcceptLanguages, this);
       break;
     }
     case NotificationType::PREF_CHANGED: {
@@ -342,6 +342,8 @@ void TranslateManager::InitiateTranslation(TabContents* tab,
   if (!prefs->GetBoolean(prefs::kEnableTranslate))
     return;
 
+  pref_change_registrar_.Init(prefs);
+
   // Allow disabling of translate from the command line to assist with
   // automated browser testing.
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kDisableTranslate))
@@ -534,7 +536,7 @@ bool TranslateManager::IsAcceptLanguage(TabContents* tab,
     notification_registrar_.Add(this, NotificationType::PROFILE_DESTROYED,
                                 Source<Profile>(tab->profile()));
     // Also start listening for changes in the accept languages.
-    tab->profile()->GetPrefs()->AddPrefObserver(prefs::kAcceptLanguages, this);
+    pref_change_registrar_.Add(prefs::kAcceptLanguages, this);
 
     iter = accept_languages_.find(pref_service);
   }