Remove PrefObserver usages, batch 12.

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

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_app.h
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_app.h b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_app.h
index 8722d79ba2a7403043e7616336e9b91ff71dbb9a..2d61d90b299971f55359c853f4f3cd4f168524c5 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_app.h
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_app.h
@@ -17,7 +17,6 @@
 #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"
@@ -60,7 +59,6 @@ class ChromeLauncherControllerPerApp
       public ash::ShellObserver,
       public ChromeLauncherController,
       public content::NotificationObserver,
-      public PrefObserver,
       public PrefServiceObserver,
       public AppSyncUIStateObserver {
  public:
@@ -235,10 +233,6 @@ class ChromeLauncherControllerPerApp
                        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;