RFR (S): 8227563: jvmti/scenarios/contention/TC05/tc05t001 fails ...

[David Holmes]

Bug: https://bugs.openjdk.java.net/browse/JDK-8227563
webrev: http://cr.openjdk.java.net/~dholmes/8227563/webrev/

See bug report for gory details. Basically on Windows thread-cpu-time 
may only get updated at the resolution of the timer interrupt, which may 
be as long as 16ms. The test checks that the elapsed cpu time is < 10ms 
and so would fail if the first and second calls to get the time 
straddled a timer interrupt (and normally it passes because both calls 
return zero).

Fix is to bump the allowed time to 16ms on Windows.

I also corrected a comment as to why part of the test is already 
disabled on Windows, and enabled verbose logging so that if this test 
fails again it will be much easier to see why.

Testing: itself, on Windows numerous times

Thanks,
David