Update to Drupal 8.2.5. For more information, see https://www.drupal.org/project/drupal/releases/8.2.5

core/modules/user/migration_templates/d6_profile_values.yml

@@ -3,12 +3,8 @@ label: Profile values
 class: Drupal\user\Plugin\migrate\ProfileValues
 migration_tags:
   - Drupal 6
-builder:
-  plugin: d6_profile_values
 source:
   plugin: d6_profile_field_values
-load:
-  plugin: drupal_entity
 process:
   uid: uid
 destination:

core/modules/user/src/Controller/UserAuthenticationController.php

@@ -233,7 +233,7 @@ class UserAuthenticationController extends ControllerBase implements ContainerIn
   /**
    * Logs out a user.
    *
-   * @return \Drupal\rest\ResourceResponse
+   * @return \Symfony\Component\HttpFoundation\Response
    *   The response object.
    */
   public function logout() {