child_process: guard against race condition
It is possible that the internal handleMessage() might try to send to a channel that has been closed. The result can be an AssertionError. Guard against this.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
It is possible that the internal handleMessage() might try to send to a channel that has been closed. The result can be an AssertionError. Guard against this.