Merge branch '2.8' into 3.2

* 2.8:
  [2.8] Fix issues reported by static analyse

Author: nicolas-grekas

EventListener/SessionListener.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\HttpKernel\EventListener;
 
+use Symfony\Component\HttpFoundation\Session\SessionInterface;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;