removeOnExitListener method

Stop listening on exit messages from the isolate.

void removeOnExitListener(
SendPort responsePort
)

Stop listening on exit messages from the isolate.

If a call has previously been made to addOnExitListener with the same send-port, this will unregister the port, and it will no longer receive a message when the isolate terminates. A response may still be sent until this operation is fully processed by the isolate.