public function addSuccessFlash(FilterUserResponseEvent $event)
 {
     if ($event->getRequest()->isXmlHttpRequest()) {
         return;
     }
     if (!isset(self::$successMessages[$event->getName()])) {
         throw new \InvalidArgumentException('This event does not correspond to a known flash message');
     }
     $this->session->getFlashBag()->add('success', $this->trans(self::$successMessages[$event->getName()]));
 }