/**
 * Load language files
 *
 * @param   string  $extension  The name of the extension
 * @param   string  $source     Path to the extension
 * @param   string  $base       Base path for the extension language
 *
 * @return  void
 *
 * @since   3.4
 */
protected function doLoadLanguage($extension, $source, $base = JPATH_ADMINISTRATOR)
{
    $lang = Factory::getLanguage();
    $lang->load($extension . '.sys', $source) || $lang->load($extension . '.sys', $base);
}