There are times when it's necessary for special users (moderators, admins) on a site to delete review requests. Added a "Delete" link at the bottom of the review request box that displays a confirmation dialog, allowing the user to delete the review request. Only users with the "delete_reviewrequest" permission can use this.

Also replaced the delete icon with a little red X. It stands out more and looks more menacing than the trash can.

Tried deleting a review request through the new API function, and got a Permission Denied. Went to the review request page and didn't see a "Delete" link. Then I logged in as admin and grnated my user the permission to delete review requests. Went back and saw the link. Clicked it, then confirmed, and saw that the review request went away.