Nelmio\SecurityBundle\EventListener\ContentTypeListener::onKernelResponse PHP Method

    public function onKernelResponse(FilterResponseEvent $e)
    {
        if (HttpKernelInterface::MASTER_REQUEST !== $e->getRequestType()) {
            return;
        }
        if (!$this->nosniff) {
            return;
        }
        $response = $e->getResponse();
        if ($response->isRedirection()) {
            return;
        }
        $response->headers->add(array('X-Content-Type-Options' => 'nosniff'));
    }

 protected function callListener(ContentTypeListener $listener, $path, $masterReq)
 {
     $request = Request::create($path);
     $response = new Response();
     $event = new FilterResponseEvent($this->kernel, $request, $masterReq ? HttpKernelInterface::MASTER_REQUEST : HttpKernelInterface::SUB_REQUEST, $response);
     $listener->onKernelResponse($event);
     return $response;
 }