diff --git a/core/includes/menu.inc b/core/includes/menu.inc
index 3a55eba..b678bb8 100644
--- a/core/includes/menu.inc
+++ b/core/includes/menu.inc
@@ -2700,6 +2700,7 @@ function menu_default_links_rebuild() {
       else {
         if (empty($link['route_name']) && empty($link['link_path'])) {
           $link['route_name'] = '<front>';
+          $link['link_title'] = 'THIS IS A BUG';
         }
         $menu_link = $menu_link_controller->create($link);
       }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Menu/MenuRouterTest.php b/core/modules/system/lib/Drupal/system/Tests/Menu/MenuRouterTest.php
index ab55143..b882567 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Menu/MenuRouterTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Menu/MenuRouterTest.php
@@ -62,10 +62,8 @@ function setUp() {
    */
   public function testMenuIntegration() {
     $this->doTestTitleMenuCallback();
-    $this->doTestMenuSetItem();
     $this->doTestMenuOptionalPlaceholders();
     $this->doTestMenuOnRoute();
-    $this->doTestMenuHidden();
     $this->doTestMenuGetItemNoAncestors();
     $this->doTestMenuName();
     $this->doTestMenuItemTitlesCases();
@@ -209,87 +207,6 @@ protected function doTestMenuHierarchy() {
   }
 
   /**
-   * Tests menu link depth and parents of local tasks and menu callbacks.
-   */
-  protected function doTestMenuHidden() {
-    // Verify links for one dynamic argument.
-    $query = \Drupal::entityQuery('menu_link')
-      ->condition('link_path', 'menu-test/hidden/menu', 'STARTS_WITH')
-      ->sort('link_path');
-    $result = $query->execute();
-    $menu_links = menu_link_load_multiple($result);
-
-    $links = array();
-    foreach ($menu_links as $menu_link) {
-      $links[$menu_link->link_path] = $menu_link;
-    }
-
-    $parent = $links['menu-test/hidden/menu'];
-    $depth = $parent['depth'] + 1;
-    $plid = $parent['mlid'];
-
-    $link = $links['menu-test/hidden/menu/list'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $link = $links['menu-test/hidden/menu/settings'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $link = $links['menu-test/hidden/menu/manage/%'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $parent = $links['menu-test/hidden/menu/manage/%'];
-    $depth = $parent['depth'] + 1;
-    $plid = $parent['mlid'];
-
-    $link = $links['menu-test/hidden/menu/manage/%/list'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $link = $links['menu-test/hidden/menu/manage/%/edit'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $link = $links['menu-test/hidden/menu/manage/%/delete'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    // Verify links for two dynamic arguments.
-    $query = \Drupal::entityQuery('menu_link')
-      ->condition('link_path', 'menu-test/hidden/block', 'STARTS_WITH')
-      ->sort('link_path');
-    $result = $query->execute();
-    $menu_links = menu_link_load_multiple($result);
-
-    $links = array();
-    foreach ($menu_links as $menu_link) {
-      $links[$menu_link->link_path] = $menu_link;
-    }
-
-    $parent = $links['menu-test/hidden/block'];
-    $depth = $parent['depth'] + 1;
-    $plid = $parent['mlid'];
-
-    $link = $links['menu-test/hidden/block/list'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $link = $links['menu-test/hidden/block/manage/%/%'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-
-    $parent = $links['menu-test/hidden/block/manage/%/%'];
-    $depth = $parent['depth'] + 1;
-    $plid = $parent['mlid'];
-
-    $link = $links['menu-test/hidden/block/manage/%/%/delete'];
-    $this->assertEqual($link['depth'], $depth, format_string('%path depth @link_depth is equal to @depth.', array('%path' => $link['link_path'], '@link_depth' => $link['depth'], '@depth' => $depth)));
-    $this->assertEqual($link['plid'], $plid, format_string('%path plid @link_plid is equal to @plid.', array('%path' => $link['link_path'], '@link_plid' => $link['plid'], '@plid' => $plid)));
-  }
-
-  /**
    * Test menu_get_item() with empty ancestors.
    */
   protected function doTestMenuGetItemNoAncestors() {
@@ -298,23 +215,6 @@ protected function doTestMenuGetItemNoAncestors() {
   }
 
   /**
-   * Test menu_set_item().
-   */
-  protected function doTestMenuSetItem() {
-    $item = menu_get_item('test-page');
-
-    $this->assertEqual($item['path'], 'test-page', "Path from menu_get_item('test-page') is equal to 'test-page'", 'menu');
-
-    // Modify the path for the item then save it.
-    $item['path'] = 'test-page-test';
-    $item['href'] = 'test-page-test';
-
-    menu_set_item('test-page', $item);
-    $compare_item = menu_get_item('test-page');
-    $this->assertEqual($compare_item, $item, 'Modified menu item is equal to newly retrieved menu item.', 'menu');
-  }
-
-  /**
    * Test menu maintenance hooks.
    */
   protected function doTestMenuItemHooks() {
diff --git a/core/modules/system/tests/modules/menu_test/menu_test.module b/core/modules/system/tests/modules/menu_test/menu_test.module
index eb3a9de..0f40f40 100644
--- a/core/modules/system/tests/modules/menu_test/menu_test.module
+++ b/core/modules/system/tests/modules/menu_test/menu_test.module
@@ -323,8 +323,6 @@ function menu_test_default_menu_links() {
   // This item tests using a description callback.
   $items['menu_callback_description.description-callback'] = array(
     'link_title' => 'Menu item with a description set with a callback',
-    'description callback' => 'check_plain',
-    'description arguments' => array('<strong>Menu item description arguments</strong>'),
     'route_name' => 'menu_test.callback_description_callback',
     'parent' => 'menu_callback_description',
   );
@@ -332,8 +330,6 @@ function menu_test_default_menu_links() {
   $items['menu_no_title_callback'] = array(
     'link_title' => 'A title with @placeholder',
     'title' => 'A title with @placeholder',
-    'title callback' => FALSE,
-    'title arguments' => array('@placeholder' => 'some other text'),
     'route_name' => 'menu_test.menu_no_title_callback',
   );
 
@@ -353,12 +349,13 @@ function menu_test_default_menu_links() {
     'parent' => 'menu_test.hierarchy_parent.child',
   );
   // Path containing "exotic" characters.
-  $path = "menu-test/ -._~!$'\"()*@[]?&+%#,;=:" . // "Special" ASCII characters.
+  $exotic = " -._~!$'\"()*@[]?&+%#,;=:" . // "Special" ASCII characters.
     "%23%25%26%2B%2F%3F" . // Characters that look like a percent-escaped string.
     "éøïвβ中國書۞"; // Characters from various non-ASCII alphabets.
-  $items[$path] = array(
+  $items['menu_test.exotic_path'] = array(
     'link_title' => '"Exotic" path',
     'route_name' => 'menu_test.exotic_path',
+    'route_parameters' => array('exotic' => $exotic),
   );
 
   // Hidden tests; base parents.
@@ -390,28 +387,45 @@ function menu_test_default_menu_links() {
 
   // Menu trail tests.
   // @see MenuTrailTestCase
-  $items['menu-test/menu-trail'] = array(
+  $items['menu-test.menu-trail'] = array(
     'link_title' => 'Menu trail - Case 1',
     'route_name' => 'menu_test.menu_trail',
     'parent' => 'menu-test',
   );
-  $items['admin/config/development/menu-trail'] = array(
+  $items['admin.config.development.menu-trail'] = array(
     'link_title' => 'Menu trail - Case 2',
     'description' => 'Tests menu_tree_set_path()',
     'route_name' => 'menu_test.menu_trail_admin',
     'parent' => 'admin.config.development',
   );
-  $items['menu-test/custom-403-page'] = array(
+  $items['menu-test.custom-403-page'] = array(
     'link_title' => 'Custom 403 page',
     'route_name' => 'menu_test.custom_403',
     'parent' => 'menu-test',
   );
-  $items['menu-test/custom-404-page'] = array(
+  $items['menu-test.custom-404-page'] = array(
     'link_title' => 'Custom 404 page',
     'route_name' => 'menu_test.custom_404',
     'parent' => 'menu-test',
   );
-
+  // Test the access key.
+  $items['menu-title-test.case1'] = array(
+    'link_title' => 'Example title - Case 1',
+    'route_name' => 'menu_test.title_test_case1',
+  );
+  $items['menu-title-test.case2'] = array(
+    'link_title' => 'Example @sub1 - Case @op2',
+    'route_name' => 'menu_test.title_test_case2',
+  );
+  $items['menu-title-test.case3'] = array(
+    'link_title' => 'Example title',
+    'route_name' => 'menu_test.title_test_case3',
+  );
+  $items['menu-title-test.case4'] = array(
+    // Title gets completely ignored. Good thing, too.
+    'link_title' => 'Bike sheds full of blue smurfs',
+    'route_name' => 'menu_test.title_test_case4',
+  );
   return $items;
 }