[Security] use LegacyEventDispatcherProxy

Author: dmaicher

Firewall/ContextListener.php

@@ -13,6 +13,7 @@
 
 use Psr\Log\LoggerInterface;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Component\EventDispatcher\LegacyEventDispatcherProxy;
 use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
 use Symfony\Component\HttpKernel\Event\RequestEvent;
 use Symfony\Component\HttpKernel\KernelEvents;
@@ -63,7 +64,7 @@ public function __construct(TokenStorageInterface $tokenStorage, iterable $userP
         $this->userProviders = $userProviders;
         $this->sessionKey = '_security_'.$contextKey;
         $this->logger = $logger;
-        $this->dispatcher = $dispatcher;
+        $this->dispatcher = LegacyEventDispatcherProxy::decorate($dispatcher);
         $this->trustResolver = $trustResolver ?: new AuthenticationTrustResolver(AnonymousToken::class, RememberMeToken::class);
     }