RFR 8235515: TestBasicLogOutput.java crashes due to EXCEPTION_ACCESS_VIOLATION in HandshakeThreadsOperation::do_handshake

[Patricio Chilano]

Hi,

Could you review this small fix? Signaling the _done semaphore has to be 
done after logging, otherwise we could be accessing an already destroyed 
HandshakeThreadsOperation object when executing name().

Bug: https://bugs.openjdk.java.net/browse/JDK-8235515
Webrev: http://cr.openjdk.java.net/~pchilanomate/8235515/v01/webrev/

Thanks!
Patricio