Code standard fixes

Author: GDIBass

src/Symfony/Component/Workflow/EventListener/GuardListener.php

@@ -12,7 +12,6 @@
 namespace Symfony\Component\Workflow\EventListener;
 
 use Symfony\Component\Security\Core\Authentication\AuthenticationTrustResolverInterface;
-use Symfony\Component\Security\Core\Authentication\Token\AnonymousToken;
 use Symfony\Component\Security\Core\Authentication\Token\Storage\TokenStorageInterface;
 use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;
 use Symfony\Component\Security\Core\Role\RoleHierarchyInterface;
@@ -57,7 +56,7 @@ private function getVariables(GuardEvent $event)
         $token = $this->tokenStorage->getToken();
 
         if (null === $token) {
-            throw new \Exception("No token is set");
+            throw new \Exception('No token is set');
         }
 
         if (null !== $this->roleHierarchy) {