13 RFR (S): 8223736:

[serguei.spitsyn at oracle.com]

Please review a fix for test bug:
   https://bugs.openjdk.java.net/browse/JDK-8223736

Webrev:
http://cr.openjdk.java.net/~sspitsyn/webrevs/2019/8223736-mon-events-test.1/

Summary:
  It seems that waiting for 0.5 sec for a MonitorContendedEnter event in the
  increment() method sometime is not enough (especially when the JFR is 
enabled).
  The fix implement an approach to ensure the event has posted before 
the worker
  thread goes to the next iteration.
  Also, another check is added to diagnose if any of two worker threads
  (tc04t001Thread) has been interrupted by timeout.
  In fact, we have many other tests which miss this kind of check and 
diagnostics.
  We may want to consider fixing other cases if we encounter this 
eventually happens.

Testing:
  A mach5 test submission is in progress.

Thanks,
Serguei