Form submission handler for contact_category_delete_form().
function contact_category_delete_form_submit($form, &$form_state) {
$category = $form_state['contact_category'];
$category
->delete();
drupal_set_message(t('Category %label has been deleted.', array(
'%label' => $category
->label(),
)));
watchdog('contact', 'Category %label has been deleted.', array(
'%label' => $category
->label(),
), WATCHDOG_NOTICE);
$form_state['redirect'] = 'admin/structure/contact';
}