Worker::childChangedStatus may lose child after enqueued

void Worker::childChangedStatus(Worker *task, const Status &status)

{      enqueue(FUNCTION_TO_QUEUE(Worker::_childChangedStatus), task, status); }

W.r.t. the above method, the child, "task" in the argument, may lose RefCount after the method returns. This could cause child "task" invalid when the method, _childChangedStatus, on the parent is dequeued from the mailbox.