Remove PrefObserver usages, batch 12.

chrome/browser/ui/alternate_error_tab_observer.cc

Index: chrome/browser/ui/alternate_error_tab_observer.cc
diff --git a/chrome/browser/ui/alternate_error_tab_observer.cc b/chrome/browser/ui/alternate_error_tab_observer.cc
index 569a739389972154f8eed7b7af5e64e29d325f68..6bac4c32d1d8a29081c3ddccaf34bc91e9291d12 100644
--- a/chrome/browser/ui/alternate_error_tab_observer.cc
+++ b/chrome/browser/ui/alternate_error_tab_observer.cc
@@ -25,7 +25,11 @@ AlternateErrorPageTabObserver::AlternateErrorPageTabObserver(
   PrefService* prefs = profile_->GetPrefs();
   if (prefs) {
     pref_change_registrar_.Init(prefs);
-    pref_change_registrar_.Add(prefs::kAlternateErrorPagesEnabled, this);
+    pref_change_registrar_.Add(
+        prefs::kAlternateErrorPagesEnabled,
+        base::Bind(&AlternateErrorPageTabObserver::
+                       OnAlternateErrorPagesEnabledChanged,
+                   base::Unretained(this)));
   }
 
   registrar_.Add(this, chrome::NOTIFICATION_GOOGLE_URL_UPDATED,
@@ -61,17 +65,6 @@ void AlternateErrorPageTabObserver::Observe(
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-// PrefObserver overrides
-
-void AlternateErrorPageTabObserver::OnPreferenceChanged(
-    PrefServiceBase* service,
-    const std::string& pref_name) {
-  DCHECK_EQ(profile_->GetPrefs(), service);
-  DCHECK(prefs::kAlternateErrorPagesEnabled == pref_name);
-  UpdateAlternateErrorPageURL(web_contents()->GetRenderViewHost());
-}
-
-////////////////////////////////////////////////////////////////////////////////
 // Internal helpers
 
 GURL AlternateErrorPageTabObserver::GetAlternateErrorPageURL() const {
@@ -90,6 +83,10 @@ GURL AlternateErrorPageTabObserver::GetAlternateErrorPageURL() const {
   return url;
 }
 
+void AlternateErrorPageTabObserver::OnAlternateErrorPagesEnabledChanged() {
+  UpdateAlternateErrorPageURL(web_contents()->GetRenderViewHost());
+}
+
 void AlternateErrorPageTabObserver::UpdateAlternateErrorPageURL(
     RenderViewHost* rvh) {
   rvh->SetAltErrorPageURL(GetAlternateErrorPageURL());