RFR: 8190353: [Testbug] test/hotspot/jtreg/gc/logging/TestPrintReferences.java can still fail

[Stefan Johansson]

Hi,

Please review this fix for:
https://bugs.openjdk.java.net/browse/JDK-8190353

Webrev:
http://cr.openjdk.java.net/~sjohanss/8190353/00/

Summary:
The fix for JDK-8188245 was incomplete, it removed the check that if the 
reported time is longer than the sum of the sub-phases everything is ok. 
The new code requires the sum of the sub-phases to be within a give 
tolerance from the reported time. This is true in many cases but we 
can't know for sure that we won't get a context switch or some other 
stall between two sub-phases that causes the reported total time to be 
longer, but the sub-phases to not include this extra time.

Testing:
Verified that the new verification method returns correct values for 
different input values.

Thanks,
Stefan