Update Status Switches to use get_post_status_object()

[wpsmith]

There are a couple places that contain switches for Post Statuses. These should be updated to use get_post_status_object() to enable more flexiblity and utilize the register_post_status() function of WordPress 3.0.

For example, in meta-boxes.php (wp-admin/includes), the status of a post/page/custom post type must be manipulated via jQuery when a status could simply be created and utilized within WordPress to use a new status like 'expired' or 'under-review'. Or consider a news company with edit revision cycles. These revisions don't appear unless there is a jquery hack in place.

[wpsmith]

Related #12706