diff --git a/core/modules/system/src/Tests/Menu/MenuTreeStorageTest.php b/core/modules/system/src/Tests/Menu/MenuTreeStorageTest.php
index 1df4050..57f1f2a 100644
--- a/core/modules/system/src/Tests/Menu/MenuTreeStorageTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuTreeStorageTest.php
@@ -354,7 +354,6 @@ protected function addMenuLink($id, $parent = '', $route_name = 'test', $route_p
       'menu_name' => $menu_name,
       'route_name' => $route_name,
       'route_parameters' => $route_parameters,
-      'title_arguments' => array(),
       'title' => 'test',
       'parent' => $parent,
       'options' => array(),
diff --git a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
index fb365f0..7b19bf0 100644
--- a/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
+++ b/core/modules/system/src/Tests/Update/UpdatePathTestBase.php
@@ -185,7 +185,14 @@ protected function runUpdates() {
       $this->fail('Missing zlib requirement for upgrade tests.');
       return FALSE;
     }
-    $this->drupalLogin($this->rootUser);
+
+    // The site might be broken at the time so logging in using the UI might
+    // not work, so we use the API itself.
+    drupal_rewrite_settings(['settings' => ['update_free_access' => (object) [
+      'value' => TRUE,
+      'required' => TRUE,
+    ]]]);
+
     $this->drupalGet($this->updateUrl);
     $this->clickLink(t('Continue'));
 
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 6d3c888..91ca627 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -8,6 +8,7 @@
 use Drupal\Component\Utility\Crypt;
 use Drupal\Component\Utility\Environment;
 use Drupal\Component\Utility\SafeMarkup;
+use Drupal\Core\StringTranslation\TranslationWrapper;
 use Drupal\Core\Url;
 use Drupal\Core\Database\Database;
 use Drupal\Core\DrupalKernel;
@@ -1107,10 +1108,58 @@ function system_update_8001() {
       'serialize' => TRUE,
     );
     db_change_field('menu_tree', 'description', 'description', $spec);
-    db_update('menu_tree')
-      ->fields(array('title' => NULL, 'description' => NULL))
+  }
+}
+
+/**
+ * Update the {menu_tree} table to convert the serialized data.
+ */
+function system_update_8002(&$sandbox = NULL) {
+  $database = \Drupal::database();
+  if (!isset($sandbox['progress'])) {
+    $sandbox['progress'] = 0;
+    // Start at 1 to skip the anonymous user.
+    $sandbox['current'] = 1;
+    $sandbox['max'] = $database->query('SELECT COUNT(*) FROM {menu_tree}')->fetchField();
+  }
+
+  $menu_links = $database->queryRange('SELECT * FROM {menu_tree} ORDER BY mlid ASC', $sandbox['current'], $sandbox['current'] + 10)->fetchAllAssoc('mlid');
+
+  $return = [];
+  foreach ($menu_links as $menu_link) {
+    $menu_link['title_arguments'] = unserialize($menu_link['title_arguments']);
+    $menu_link['title_context'] = unserialize($menu_link['title_context']);
+
+    // Convert static defined plugins to use t().
+    if ($menu_link['class'] === 'Drupal\Core\Menu\MenuLinkDefault') {
+      $menu_link['title'] = serialize(new TranslationWrapper($menu_link['title'], $menu_link['title_arguments'], ['context' => $menu_link['title_context']]));
+    }
+    else {
+      $menu_link['title'] = serialize($menu_link['title']);
+    }
+    $menu_link['description'] = serialize($menu_link['description']);
+
+    unset($menu_link['title_arguments']);
+    unset($menu_link['title_context']);
+
+    $database->update('menu_tree')
+      ->fields($menu_link)
+      ->condition('mlid', $menu_link['mlid'])
       ->execute();
-    db_drop_field('menu_tree', 'title_arguments');
-    db_drop_field('menu_tree', 'title_context');
+
+    $sandbox['progress']++;
+    $sandbox['current']++;
   }
-}
\ No newline at end of file
+
+  $return['#finished'] = empty($sandbox['max']) ? 1 : ($sandbox['current'] / $sandbox['max']);
+
+  return $return;
+}
+
+/**
+ * Drop unnecessary fields from {menu_tree}.
+ */
+function system_update_8003() {
+  db_drop_field('menu_tree', 'title_arguments');
+  db_drop_field('menu_tree', 'title_context');
+}