[11u] RFR: 8234742: Improve handshake logging

[Doerr, Martin]

Hi,

JDK-8234742 is backported to 11.0.11-oracle. I'd like to backport it for parity.
Change doesn't apply cleanly at all, mainly because JDK-8244340 was integrated before this one which was in the wrong order.
(Failing hunks are listed here: http://cr.openjdk.java.net/~mdoerr/8234742_handshake_11u/8234742_handshake_failing_hunks.txt)
So my 11u backport is supposed to reflect the state of both changes integrated.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8234742

Original change:
https://hg.openjdk.java.net/jdk/jdk/rev/c2ce3849c62f

Other change which was backported in the wrong order and from which I've taken small parts:
https://hg.openjdk.java.net/jdk/jdk/rev/67a435ce2dc2

11u backport:
http://cr.openjdk.java.net/~mdoerr/8234742_handshake_11u/webrev.00/

Please review.

Best regards,
Martin