diff --git a/core/lib/Drupal/Core/StackMiddleware/Session.php b/core/lib/Drupal/Core/StackMiddleware/Session.php
deleted file mode 100644
index f8a1970..0000000
--- a/core/lib/Drupal/Core/StackMiddleware/Session.php
+++ /dev/null
@@ -1,57 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\Core\StackMiddleware\Session.
- */
-
-namespace Drupal\Core\StackMiddleware;
-
-use Drupal\Core\Session\SessionManagerInterface;
-use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\HttpKernel\HttpKernelInterface;
-
-/**
- * Executes the page caching before the main kernel takes over the request.
- */
-class Session implements HttpKernelInterface {
-
-  /**
-   * The wrapped HTTP kernel.
-   *
-   * @var \Symfony\Component\HttpKernel\HttpKernelInterface
-   */
-  protected $httpKernel;
-
-  /**
-   * The session manager.
-   *
-   * @var \Drupal\Core\Session\SessionManagerInterface
-   */
-  protected $drupalKernel;
-
-  /**
-   * Constructs a Session stack middleware object.
-   *
-   * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
-   *   The decorated kernel.
-   * @param \Drupal\Core\Session\SessionManagerInterface $session_manager
-   *   The session manager.
-   */
-  public function __construct(HttpKernelInterface $http_kernel, SessionManagerInterface $session_manager) {
-    $this->httpKernel = $http_kernel;
-    $this->sessionManager = $session_manager;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE) {
-    $this->sessionManager->startLazy();
-    $result = $this->httpKernel->handle($request, $type, $catch);
-    $this->sessionManager->save();
-
-    return $result;
-  }
-
-}