wp-notices.php
private function restore_user( $id ) {
		$id     = self::$instance->get_id( $id );
		$notice = self::$instance->get_notice( $id );

		if ( false === $notice ) {
			return false;
		}

		$dismissed = self::$instance->dismissed_user();
		if ( ! in_array( $id, $dismissed ) ) {
			return false;
		}

		$flip = array_flip( $dismissed );
		$key  = $flip[ $id ];
		unset( $dismissed[ $key ] );

		return update_user_meta( get_current_user_id(), 'tdp_dismissed_notices', $dismissed );
	}
private function restore_user( $id ) {
		$id     = self::$instance->get_id( $id );
		$notice = self::$instance->get_notice( $id );

		if ( false === $notice ) {
			return false;
		}

		$dismissed = self::$instance->dismissed_user();
		if ( ! in_array( $id, $dismissed ) ) {
			return false;
		}

		$flip = array_flip( $dismissed );
		$key  = $flip[ $id ];
		unset( $dismissed[ $key ] );

		return update_user_meta( get_current_user_id(), 'tdp_dismissed_notices', $dismissed );
	}
Restore a notice for the current user.

@param string $id the id of the notice.
@return void