ages or all of them.
	 *
	 * @since 4.9.11
	 *
	 * @param null|string $type     The type of message to reset, or `null` to reset all messages.
	 * @param null|int    $priority The specific priority to reset, this will be ignored if the `$type` parameter
	 *                              is not set.
	 */
	public function reset( $type = null, $priority = null ) {
		if ( null !== $type && isset( $this->messages[ $type ] ) ) {
			if ( null !== $priority ) {
				if ( isset( $this->messages[ $type ][ $priority ] ) ) {
					unset( $this->messages[ $type ][ $priority ] );
				}
			} else {
				unset( $this->messages[ $type ] );
			}
		} else {
			$this->messages = [];
		}
	}
}