Issue #2917331 by catch, martin107, Deepak Goyal, longwave, andypost,...

use Symfony\Component\HttpFoundation\Request;

use Symfony\Component\HttpFoundation\Response;

use Drupal\Core\Site\Settings;

use Symfony\Cmf\Component\Routing\RouteObjectInterface;

use Drupal\Core\Routing\RouteObjectInterface;

use Symfony\Component\Routing\Route;

// Change the directory to the Drupal root.

use Drupal\Core\DependencyInjection\ContainerBuilder;

use Drupal\Core\Url;

use Drupal\language\Entity\ConfigurableLanguage;

use Symfony\Cmf\Component\Routing\RouteObjectInterface;

use Drupal\Core\Routing\RouteObjectInterface;

use Symfony\Component\DependencyInjection\Reference;

use Symfony\Component\HttpFoundation\Request;

use Symfony\Component\HttpFoundation\Response;

use Drupal\Component\Utility\ArgumentsResolverInterface;

use Symfony\Component\HttpFoundation\Request;

use Symfony\Component\Routing\Exception\RouteNotFoundException;

use Symfony\Cmf\Component\Routing\RouteObjectInterface;

use Drupal\Core\Routing\RouteObjectInterface;

/**

 * Attaches access check services to routes and runs them on request.

use Drupal\Core\Routing\EnhancerInterface;

use Symfony\Component\HttpFoundation\Request;

use Symfony\Cmf\Component\Routing\RouteObjectInterface;

use Drupal\Core\Routing\RouteObjectInterface;

use Symfony\Component\Routing\Route;

/**

namespace Drupal\Core\EventSubscriber;

use Symfony\Cmf\Component\Routing\RouteProviderInterface;

use Drupal\Core\Routing\RouteProviderInterface;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;

use Symfony\Component\HttpFoundation\Response;

use Symfony\Component\HttpKernel\Event\RequestEvent;

  /**

   * The route provider.

   *

   * @var \Symfony\Cmf\Component\Routing\RouteProviderInterface

   * @var \Drupal\Core\Routing\RouteProviderInterface

   */

  protected $routeProvider;

  /**

   * Creates a new OptionsRequestSubscriber instance.

   *

   * @param \Symfony\Cmf\Component\Routing\RouteProviderInterface $route_provider

   * @param \Drupal\Core\Routing\RouteProviderInterface $route_provider

   *   The route provider.

   */

  public function __construct(RouteProviderInterface $route_provider) {