Issue #2701769 by snufkin: Missing @return documentation from ContentTranslationHandler::entityFormTitle

(cherry picked from commit c28aa40f54)

core/modules/content_translation/src/ContentTranslationHandler.php

@@ -696,6 +696,9 @@ class ContentTranslationHandler implements ContentTranslationHandlerInterface, E
    *
    * @param \Drupal\Core\Entity\EntityInterface $entity
    *   The entity whose form is being altered.
+   *
+   * @return string|null
+   *   The label of the entity, or NULL if there is no label defined.
    */
   protected function entityFormTitle(EntityInterface $entity) {
     return $entity->label();