/**
  * @param GetResponseEvent $event
  */
 public function onKernelRequest(GetResponseEvent $event)
 {
     if (HttpKernelInterface::MASTER_REQUEST !== $event->getRequestType()) {
         // don't do anything if it's not the master request
         return;
     }
     $this->deviceDetection->setUserAgent($event->getRequest()->headers->get('User-Agent'));
 }