Remove PrefObserver usages, batch 13.

chrome/browser/ui/webui/options/content_settings_handler.cc

Index: chrome/browser/ui/webui/options/content_settings_handler.cc
diff --git a/chrome/browser/ui/webui/options/content_settings_handler.cc b/chrome/browser/ui/webui/options/content_settings_handler.cc
index f1537732feee71232d500446706f27e4b88aa58a..5e217c3e29a3c8725b5428ee61c53c0877b1fcf4 100644
--- a/chrome/browser/ui/webui/options/content_settings_handler.cc
+++ b/chrome/browser/ui/webui/options/content_settings_handler.cc
@@ -488,7 +488,11 @@ void ContentSettingsHandler::InitializeHandler() {
 
   PrefService* prefs = profile->GetPrefs();
   pref_change_registrar_.Init(prefs);
-  pref_change_registrar_.Add(prefs::kPepperFlashSettingsEnabled, this);
+  pref_change_registrar_.Add(
+      prefs::kPepperFlashSettingsEnabled,
+      base::Bind(&ContentSettingsHandler::RefreshFlashSettingsCache,
+                 base::Unretained(this),
+                 false));
 
   flash_settings_manager_.reset(new PepperFlashSettingsManager(this, profile));
 }
@@ -556,12 +560,6 @@ void ContentSettingsHandler::Observe(
   }
 }
 
-void ContentSettingsHandler::OnPreferenceChanged(PrefServiceBase* service,
-                                                 const std::string& pref_name) {
-  DCHECK_EQ(pref_name, std::string(prefs::kPepperFlashSettingsEnabled));
-  RefreshFlashSettingsCache(false);
-}
-
 void ContentSettingsHandler::OnGetPermissionSettingsCompleted(
     uint32 request_id,
     bool success,