JIRA: https://jira.spring.io/browse/INT-3654
Previously, single-use `TcpConnections` self-closed when their use was complete.
This is unnatural and caused issues such as INT-3722.
Remove the self-closing behavior; connection close is now (properly) the responsibility
of the client using the connection:
- Client Side:
-- `TcpOutboundGateway` after the reply is received
-- `TcpSendingMessageHandler` after the send, when there is no collaborating inbound adapter
-- `TcpReceivingChannelAdapter` when it is collaborating (after receiving the reply)
- Server Side:
-- `TcpInboundGateway` after the reply is sent
-- `TcpReceivingChannelAdapter` after the receive, when there is no collaborating outbound adapter
-- `TcpSendingMessageHandler` when it is colllaborating (after sending the reply)
As before, the `CachingClientConnectionFactory` always sets single use on the target factory
to force it to create new connections on demand. It is always a single-use factory itself
so the clients return the connections to the pool (via `close()`).
__Needs a migration guide entry__
INT-3654: Fix Late Listener Registration
Timing failures in `TcpOutboundGatewayTests.testFailoverCached()` (null listener).
The `FailoverClientConnectionFactory` registers its listener with the actual
connections it retrieves from a delegate.
When nesting failover and cached connection factories, we need to propagate the
`enableManualListenerRegistration` to the delegate factories so the connection
will wait for its listener to be registered.
ec5230abc7