Controller "ez_content:viewLocation" for URI "/" is not callable.

services.yml

parameters:
    custom.view_controller.class: Cleverti\OverrideViewControllerBundle\Controller\ViewController

services:
    custom.view_controller:
        class: %custom.view_controller.class%

    ez_content:
        alias: custom.view_controller

ViewController.php

<?php

namespace Cleverti\OverrideViewControllerBundle\Controller;

use Symfony\Component\HttpFoundation\Response;
use eZ\Bundle\EzPublishCoreBundle\Controller;

/**
 * Description of ViewController
 *
 * @author Pedro Resende <pedroresende@ez.no>
 */
class ViewController extends Controller
{

    public function viewLocationAction( $locationId, $viewType, $layout = false, array $params = array() )
    {
        $response = $this->get('ez_content')->viewLocation($locationId, $viewType, $layout, $params);

        $response->setContent($response->getContent());
        $response->setETag(md5($response->getContent()));
        $response->setPrivate();

        return $response;
    }
}