RFR 8219616: [TESTBUG] runtime/CompressedOops/UseCompressedOops.java failed on Windows when getting disjoint instead of zero based coops

[Harold Seigel]

Hi,

Please review this backport of the fix for JDK-8079353 
<https://bugs.openjdk.java.net/browse/JDK-8079353> to JDK-12u.  The 
patch for the test applied cleanly. Additionally, the changed test was 
run 500+ with JDK-12u without a failure.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8219616_12u/webrev/index.html

JBS Bug:  https://bugs.openjdk.java.net/browse/JDK-8219616

Thanks! Harold