Remove PrefObserver usages, batch 12.

chrome/browser/ui/ash/launcher/chrome_launcher_controller.h

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller.h
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.h b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.h
index 9d438fb3c34f1cf5cbe65ce9a0d7b9c122dcf50a..320b519c00a275a7959ea8d8993d98e08735fb23 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.h
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.h
@@ -18,7 +18,6 @@
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/public/pref_change_registrar.h"
-#include "base/prefs/public/pref_observer.h"
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/prefs/pref_service_observer.h"
 #include "chrome/browser/ui/ash/app_sync_ui_state_observer.h"
@@ -58,7 +57,6 @@ class ChromeLauncherController
       public ash::LauncherModelObserver,
       public ash::ShellObserver,
       public content::NotificationObserver,
-      public PrefObserver,
       public PrefServiceObserver,
       public AppSyncUIStateObserver {
  public:
@@ -267,10 +265,6 @@ class ChromeLauncherController
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
-  // Overridden from PrefObserver:
-  virtual void OnPreferenceChanged(PrefServiceBase* service,
-                                   const std::string& pref_name) OVERRIDE;
-
   // Overridden from ash::ShellObserver:
   virtual void OnShelfAlignmentChanged() OVERRIDE;