symfony: WebProfiler JS error when updating request in kernel.event_controller

Q	A
Bug report?	yes
Feature request?	no
BC Break report?	no
RFC?	no
Symfony version	4.0.4

Hi,

For some reasons, i use the onKernelController method to initiate some stuff, but when i want to alterate the request (updating one parameter), i got a JS error in my console and the debug toolbar doesn’t appear :

Uncaught TypeError: Cannot read property 'nodeValue' of null
    at Sfjs.load.maxTries (login:867)
    at login:867
    at XMLHttpRequest.xhr.onreadystatechange (login:867)

This is my code :

public function onKernelController(FilterControllerEvent $event) {
    if(null === $user) {
        // These 2 lines provide the JS error !
	$event->getRequest()->attributes->set('_controller', 'App\CommonBundle\Controller\SecurityController::login');
	$event->getRequest()->attributes->set('_route', '/login');
                        
        // If this is alone, i have no error
	$event->setController($this->resolver->getController($event->getRequest()));
	}
}

Thanks for your help !