se agrego un use

Controller/OAuthController.php

@@ -4,6 +4,7 @@ namespace Base\OAuthBundle\Controller;
 
 use Symfony\Bundle\FrameworkBundle\Controller\Controller;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
 use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
 
 class OAuthController extends Controller