CANCELING.onCanceled() never triggered when being stopped before connecting

[sam-ma]

Consider the case when TcpTransport.stop() is called just after a TcpTransport.start() call. There is a chance that the socketState becomes CANCELING which is changed by the TcpTransport.stop() call. The following logic would prevent it from connecting and doing any further initialization. In this scenario, the CANCELING.onCanceled() would never be triggered after that, which means the onCompleted Task of the TcpTransport.stop() parameter would never be triggered as well. As a result, the client will wait forever if it relies on the onCompleted Task to be called to proceed.

// No need to complete if we have been canceled.
if( ! socketState.is(CONNECTING.class) ) {
    return;
}

[sam-ma]

I believe AMQ-6405 will be fixed by this pull request.