There's no point in sending a cancel message to the remote linked task
and especially no reason to block waiting on a result from that task if
the transport layer is detected to be disconnected. We expect that the
transport shouldn't go down at the layer of the message loop
(reconnection logic should be handled in the transport layer itself) so
if we detect the channel is not connected we don't bother requesting
cancels nor waiting on a final result message.
Why?
- if the connection goes down in error the caller side won't have a way
to know "how long" it should block to wait for a cancel ack or result
and causes a potential hang that may require an additional ctrl-c from
the user especially if using the debugger or if the traceback is not
seen on console.
- obviously there's no point in waiting for messages when there's no
transport to deliver them XD
Further, add some more detailed cancel logging detailing the task and
actor ids.
02210d8f8e