Issue #3071143: Add #footer and #caption information.

core/lib/Drupal/Core/Render/Element/Table.php

@@ -24,6 +24,8 @@
  *   providing responsive tables.  Defaults to TRUE.
  * - #sticky: Indicates whether to add the drupal.tableheader library that makes
  *   table headers always visible at the top of the page. Defaults to FALSE.
+ * - #footer: Table footer rows, in the same format as the rows variable.
+ * - #caption: A localized string for the <caption> tag.
  *
  * Usage example 1: A simple form with an additional information table which
  * doesn't include any other form field.