jmx-dev RFR: 6815130 intermittent ThreadMXBean/Locks.java failure

[Jaroslav Bachorik]

Please, review the following patch of the intermittently failing test:
http://cr.openjdk.java.net/~jbachorik/6815130/webrev.01

Issue: https://bugs.openjdk.java.net/browse/JDK-6815130


Sometimes the ThreadExecutionSynchronizer class failes to achieve the
desired synchronization (due to possible data races when evaluating and
setting the "waiting" variable) leading to test failures.

The patch fixes the possibility of data race. Also the Locks class is
tidied up a bit.

Thanks,

-JB-