Dummy shutdown function.
function _system_test_second_shutdown_function($arg1, $arg2) {
  // Output something, page has already been printed and the session stored
  // so we can't use drupal_set_message.
  print t('Second shutdown function, arg1 : @arg1, arg2: @arg2', array(
    '@arg1' => $arg1,
    '@arg2' => $arg2,
  ));
  // Throw an exception with an HTML tag. Since this is called in a shutdown
  // function, it will not bubble up to the default exception handler but will
  // be caught in _drupal_shutdown_function() and be displayed through
  // _drupal_render_exception_safe().
  throw new Exception('Drupal is <blink>awesome</blink>.');
}