connection.* methods should not ignore AlreadyClosedException

The change got lost earlier during branch re-creation.
Backed out changeset 39d010399f9d

When network connection fails right before a connection negotiation/tuning
frame is sent, we want OperationInterruptedException to be thrown and not
AlreadyClosedException.

SessionBase#Transmit will throw the latter,
if we handle it, method continuation will eventually throw an OIE.
Replace confusing comments
Merge bug26071