Requests that the parent window refreshes a particular page region.
$region: The name of the page region to refresh. The parent window will trigger a refresh of this region on the next page load.
Drupal.overlay.refreshRegions()
function overlay_request_refresh($region) {
$class = drupal_region_class($region);
$_SESSION['overlay_regions_to_refresh'][] = array(
$class => $region,
);
}