diff --git a/core/modules/simpletest/src/RouteBuilder.php b/core/modules/simpletest/src/RouteBuilder.php
index 3672af4..3b7100f 100644
--- a/core/modules/simpletest/src/RouteBuilder.php
+++ b/core/modules/simpletest/src/RouteBuilder.php
@@ -8,7 +8,6 @@
 namespace Drupal\simpletest;
 
 use Drupal\Core\DependencyInjection\DependencySerializationTrait;
-use Drupal\Core\DestructableInterface;
 use Drupal\Core\Routing\RouteBuilderInterface;
 
 /**
@@ -16,67 +15,48 @@
  *
  * @see \Drupal\Component\ProxyBuilder
  */
-class RouteBuilder implements RouteBuilderInterface, DestructableInterface {
+class RouteBuilder implements RouteBuilderInterface {
 
   use DependencySerializationTrait;
 
   /**
+   * Flag that indicates if we should rebuild at the end of the request.
+   *
    * @var bool
    */
-  protected $tableInstalled;
+  protected $rebuildNeeded = FALSE;
 
   /**
-   * Loads the router builder and installs the router table.
-   *
-   * @param bool $table_needed
-   *   TRUE when the table needs to be installed.
-   *
-   * @return \Drupal\Core\Routing\RouteBuilderInterface|\Drupal\Core\DestructableInterface
-   *   Returns the real route builder.
+   * {@inheritdoc}
    */
-  protected function lazyLoadItself($table_needed = FALSE) {
-    if (!isset($this->service)) {
-      $container = \Drupal::getContainer();
-      $this->service = $container->get('simpletest.router.builder');
+  public function rebuildIfNeeded() {
+    if ($this->rebuildNeeded) {
+      return $this->rebuild();
     }
-    if ($table_needed && !$this->tableInstalled) {
-      $container = \Drupal::getContainer();
-      $schema = $container->get('database')->schema();
-      if (!$schema->tableExists('router')) {
-        include_once $container->get('app.root') . '/core/modules/system/system.install';
-        $schema->createTable('router', system_schema()['router']);
-        $this->tableInstalled = TRUE;
-      }
-    }
-    return $this->service;
+    return FALSE;
   }
 
   /**
    * {@inheritdoc}
    */
   public function setRebuildNeeded() {
-    return $this->lazyLoadItself()->setRebuildNeeded();
+    $this->rebuildNeeded = TRUE;
   }
 
   /**
    * {@inheritdoc}
    */
   public function rebuild() {
-    return $this->lazyLoadItself(TRUE)->rebuild();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function rebuildIfNeeded() {
-    return $this->lazyLoadItself()->rebuildIfNeeded();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function destruct() {
-    return $this->lazyLoadItself()->destruct();
+    if (!isset($this->service)) {
+      $container = \Drupal::getContainer();
+      $this->service = $container->get('simpletest.router.builder');
+      $schema = $container->get('database')->schema();
+      if (!$schema->tableExists('router')) {
+        include_once $container->get('app.root') . '/core/modules/system/system.install';
+        $schema->createTable('router', system_schema()['router']);
+      }
+    }
+    return $this->service->rebuild();
   }
 
 }
diff --git a/core/modules/simpletest/src/RouteProvider.php b/core/modules/simpletest/src/RouteProvider.php
index 04c6383..acff99a 100644
--- a/core/modules/simpletest/src/RouteProvider.php
+++ b/core/modules/simpletest/src/RouteProvider.php
@@ -9,13 +9,12 @@
 
 use Drupal\Core\Routing\PreloadableRouteProviderInterface;
 use Symfony\Cmf\Component\Routing\PagedRouteProviderInterface;
-use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\HttpFoundation\Request;
 
 /**
  * Rebuilds the router when the provider is instantiated.
  */
-class RouteProvider implements PreloadableRouteProviderInterface, PagedRouteProviderInterface, EventSubscriberInterface {
+class RouteProvider implements PreloadableRouteProviderInterface, PagedRouteProviderInterface {
 
   use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
 
@@ -101,13 +100,6 @@ public function reset() {
   /**
    * {@inheritdoc}
    */
-  public static function getSubscribedEvents() {
-    RouteProvider::getSubscribedEvents();
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function getRoutesPaged($offset, $length = NULL) {
     return $this->lazyLoadItself()->getRoutesPaged($offset, $length);
   }
diff --git a/core/modules/simpletest/src/TestServiceProvider.php b/core/modules/simpletest/src/TestServiceProvider.php
index 9f16419..e88fe9a 100644
--- a/core/modules/simpletest/src/TestServiceProvider.php
+++ b/core/modules/simpletest/src/TestServiceProvider.php
@@ -37,7 +37,9 @@ public function alter(ContainerBuilder $container) {
       // not, so do it ourselves.
       foreach (['router.route_provider' => 'RouteProvider', 'router.builder' => 'RouteBuilder'] as $original_id => $class) {
         for ($id = $original_id; $container->hasAlias($id); $id = (string) $container->getAlias($id));
-        $container->setDefinition("simpletest.$original_id", $container->getDefinition($id));
+        $definition = $container->getDefinition($id);
+        $definition->clearTag('needs_destruction');
+        $container->setDefinition("simpletest.$original_id", $definition);
         $container->setDefinition($id, new Definition('Drupal\simpletest\\' . $class));
       }
     }