Symfony2 custom exception event

config.yml

parameters:
    euphory.exceptlistener.class: Euphory\StoreBundle\Event\WebExceptionListener

services:
    euphory.exceptlistener:
        class: %euphory.exceptlistener.class%
        arguments: [@mailer,@templating,@logger]
        tags:
            - { name: kernel.event_listener, event: kernel.exception, method: onKernelException, priority: 200

listener.php

<?php

namespace Euphory\StoreBundle\Event;

use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class WebExceptionListener implements EventSubscriberInterface
{
    /**
     * @var \Swift_Mailer
     */
    protected $mailer;

    /**
     * @var \Symfony\Bundle\TwigBundle\Debug\TimedTwigEngine
     */
    protected $templating;

    /**
     * @var \Monolog\Logger
     */
    protected $logger;

    public function __construct($mailer, $templating, $logger)
    {
        $this->mailer = $mailer;
        $this->templating = $templating;
        $this->logger = $logger;
    }

    public function onKernelException(GetResponseForExceptionEvent $event)
    {
    }
}