WP_Media_List_Table::prepare_items()

	public function prepare_items() {
		global $wp_query, $post_mime_types, $avail_post_mime_types, $mode;

		list( $post_mime_types, $avail_post_mime_types ) = wp_edit_attachments_query( $_REQUEST );

 		$this->is_trash = isset( $_REQUEST['attachment-filter'] ) && 'trash' === $_REQUEST['attachment-filter'];

 		$mode = empty( $_REQUEST['mode'] ) ? 'list' : $_REQUEST['mode'];

		$this->set_pagination_args( array(
			'total_items' => $wp_query->found_posts,
			'total_pages' => $wp_query->max_num_pages,
			'per_page' => $wp_query->query_vars['posts_per_page'],
		) );
	}