/**
  * Prepares the control.
  *
  * If no tabs exist, removes the control from the manager.
  *
  * @since 3.4.2
  */
 public function prepare_control()
 {
     global $custom_image_header;
     if (empty($custom_image_header)) {
         return parent::prepare_control();
     }
     // Process default headers and uploaded headers.
     $custom_image_header->process_default_headers();
     $this->default_headers = $custom_image_header->default_headers;
     $this->uploaded_headers = get_uploaded_header_images();
     if ($this->default_headers) {
         $this->add_tab('default', __('Default'), array($this, 'tab_default_headers'));
     }
     if (!$this->uploaded_headers) {
         $this->remove_tab('uploaded');
     }
     return parent::prepare_control();
 }