diff --git a/core/lib/Drupal/Core/Form/FormSubmitter.php b/core/lib/Drupal/Core/Form/FormSubmitter.php
index b975a70..42c33a9 100644
--- a/core/lib/Drupal/Core/Form/FormSubmitter.php
+++ b/core/lib/Drupal/Core/Form/FormSubmitter.php
@@ -136,13 +136,7 @@ public function redirectForm(FormStateInterface $form_state) {
     }
     // If no redirect was specified, redirect to the current path.
     elseif ($redirect === NULL) {
-      $request = $this->requestStack->getCurrentRequest();
-      // @todo Remove dependency on the internal _system_path attribute:
-      //   https://www.drupal.org/node/2293521.
-      $url = $this->urlGenerator->generateFromPath($request->attributes->get('_system_path'), array(
-        'query' => $request->query->all(),
-        'absolute' => TRUE,
-      ));
+      $url = $this->requestStack->getCurrentRequest()->getUri();
     }
 
     if ($url) {
diff --git a/core/modules/system/src/Tests/Form/ElementsTableSelectTest.php b/core/modules/system/src/Tests/Form/ElementsTableSelectTest.php
index 9167501..51771a7 100644
--- a/core/modules/system/src/Tests/Form/ElementsTableSelectTest.php
+++ b/core/modules/system/src/Tests/Form/ElementsTableSelectTest.php
@@ -217,6 +217,7 @@ private function formSubmitHelper($form, $edit) {
     $form['#token'] = FALSE;
 
     $edit['form_id'] = $form_id;
+    $form_state->disableRedirect();
     $form_state->setUserInput($edit);
     $form_state->setFormObject(new StubForm($form_id, $form));
 
diff --git a/core/modules/system/tests/modules/theme_test/src/EventSubscriber/ThemeTestSubscriber.php b/core/modules/system/tests/modules/theme_test/src/EventSubscriber/ThemeTestSubscriber.php
index b4e4393..01fa88f 100644
--- a/core/modules/system/tests/modules/theme_test/src/EventSubscriber/ThemeTestSubscriber.php
+++ b/core/modules/system/tests/modules/theme_test/src/EventSubscriber/ThemeTestSubscriber.php
@@ -8,6 +8,7 @@
 namespace Drupal\theme_test\EventSubscriber;
 
 use Drupal\Core\Url;
+use Drupal\Core\Routing\RouteMatchInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
@@ -24,6 +25,22 @@ class ThemeTestSubscriber implements EventSubscriberInterface {
    */
   protected $container;
 
+  /**
+   * The current route match.
+   *
+   * @var \Drupal\Core\Routing\RouteMatchInterface
+   */
+  protected $currentRouteMatch;
+
+  /**
+   * Constructs a new ThemeTestSubscriber.
+   *
+   * @param \Drupal\Core\Routing\RouteMatchInterface $current_route_match
+   */
+  public function __construct(RouteMatchInterface $current_route_match) {
+    $this->currentRouteMatch = $current_route_match;
+  }
+
 
   /**
    * Generates themed output early in a page request.
@@ -31,9 +48,7 @@ class ThemeTestSubscriber implements EventSubscriberInterface {
    * @see \Drupal\system\Tests\Theme\ThemeEarlyInitializationTest::testRequestListener()
    */
   public function onRequest(GetResponseEvent $event) {
-    $request = $event->getRequest();
-    $current_path = $request->attributes->get('_system_path');
-    if ($current_path == 'theme-test/request-listener') {
+    if ($this->currentRouteMatch->getRouteName() === 'theme_test.request_listener') {
       // First, force the theme registry to be rebuilt on this page request.
       // This allows us to test a full initialization of the theme system in
       // the code below.
@@ -56,9 +71,13 @@ public function onRequest(GetResponseEvent $event) {
    * Ensures that the theme registry was not initialized.
    */
   public function onView(GetResponseEvent $event) {
-    $request = $event->getRequest();
-    $current_path = $request->attributes->get('_system_path');
-    if (strpos($current_path, 'user/autocomplete') === 0) {
+    $current_route = $this->currentRouteMatch->getRouteName();
+    $user_autcomplete_route = array(
+      'user.autocomplete',
+      'user.autocomplete_anonymous',
+    );
+
+    if (in_array($current_route, $user_autcomplete_route)) {
       if ($this->container->initialized('theme.registry')) {
         throw new \Exception('registry initialized');
       }
diff --git a/core/modules/system/tests/modules/theme_test/theme_test.services.yml b/core/modules/system/tests/modules/theme_test/theme_test.services.yml
index 69fd3ca..add8b4c 100644
--- a/core/modules/system/tests/modules/theme_test/theme_test.services.yml
+++ b/core/modules/system/tests/modules/theme_test/theme_test.services.yml
@@ -1,6 +1,7 @@
 services:
   theme_test.subscriber:
     class: Drupal\theme_test\EventSubscriber\ThemeTestSubscriber
+    arguments: [@current_route_match]
     tags:
       - { name: event_subscriber }
 
diff --git a/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php b/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
index ff2b2cd..b10d41e 100644
--- a/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
+++ b/core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
@@ -102,17 +102,14 @@ public function providerTestHandleFormSubmissionWithResponses() {
    */
   public function testRedirectWithNull() {
     $form_submitter = $this->getFormSubmitter();
-    $this->urlGenerator->expects($this->once())
-      ->method('generateFromPath')
-      ->with(NULL, array('query' => array(), 'absolute' => TRUE))
-      ->willReturn('<front>');
 
     $form_state = $this->getMock('Drupal\Core\Form\FormStateInterface');
     $form_state->expects($this->once())
       ->method('getRedirect')
       ->willReturn(NULL);
     $redirect = $form_submitter->redirectForm($form_state);
-    $this->assertSame('<front>', $redirect->getTargetUrl());
+    // If we have no redirect, we redirect to the current URL.
+    $this->assertSame('http://localhost/test-path', $redirect->getTargetUrl());
     $this->assertSame(303, $redirect->getStatusCode());
   }
 
@@ -234,7 +231,7 @@ public function testExecuteSubmitHandlers() {
    */
   protected function getFormSubmitter() {
     $request_stack = new RequestStack();
-    $request_stack->push(new Request());
+    $request_stack->push(Request::create('/test-path'));
     return $this->getMockBuilder('Drupal\Core\Form\FormSubmitter')
       ->setConstructorArgs(array($request_stack, $this->urlGenerator))
       ->setMethods(array('batchGet', 'drupalInstallationAttempted'))