sector-8.x-2.0-alpha4/modules/admin_ui_toggle/admin_ui_toggle.module

<?php

/**
 * Implements hook_theme().
 */
function admin_ui_toggle_theme($existing, $type, $theme, $path) {
  return [
    'admin_ui_toggle' => [
      'render element' => 'element',
    ],
  ];
}