Remove NOTIFICATION_EXTENSION_ENABLED.

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 843fa9198a9691d01ca0296478cf693f9431ef78..dd1ec6acdc36930e3e5fd77bcd06078a67e114aa 100644
--- a/chrome/browser/themes/theme_service.h
+++ b/chrome/browser/themes/theme_service.h
@@ -302,13 +302,6 @@ class ThemeService : public base::NonThreadSafe,
 
   scoped_refptr<CustomThemeSupplier> theme_supplier_;
 
-  // The id of the theme extension which has just been installed but has not
-  // been loaded yet. The theme extension with |installed_pending_load_id_| may
-  // never be loaded if the install is due to updating a disabled theme.
-  // |pending_install_id_| should be set to |kDefaultThemeID| if there are no
-  // recently installed theme extensions
-  std::string installed_pending_load_id_;
-
   // The number of infobars currently displayed.
   int number_of_infobars_;