Remove deprecated extension notification from theme_service

chrome/browser/themes/theme_service.h

Index: chrome/browser/themes/theme_service.h
diff --git a/chrome/browser/themes/theme_service.h b/chrome/browser/themes/theme_service.h
index b70fd74c3cdb19ec7b8f273e11b1dbbd4532cba1..b30be1e08646139ab5f79620c42c3672ef51ffae 100644
--- a/chrome/browser/themes/theme_service.h
+++ b/chrome/browser/themes/theme_service.h
@@ -92,6 +92,9 @@ class ThemeService : public base::NonThreadSafe,
   NSGradient* GetNSGradient(int id) const override;
 #endif
 
+  // KeyedService:
+  void Shutdown() override;
+
   // Overridden from content::NotificationObserver:
   void Observe(int type,
                const content::NotificationSource& source,
@@ -248,6 +251,11 @@ class ThemeService : public base::NonThreadSafe,
 
   scoped_ptr<ThemeSyncableService> theme_syncable_service_;
 
+#if defined(ENABLE_EXTENSIONS)
+  class ThemeObserver;
+  scoped_ptr<ThemeObserver> theme_observer_;
+#endif
+
   base::WeakPtrFactory<ThemeService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ThemeService);