RFR (XXS) JDK-8153578,Default NewRatio is ignored when UseConcMarkSweepGC is used as GC algorithm

[Joseph Provino]

Please review this tiny change.  It only affects ParNew.  Are there any 
unintended consequences?

Passes JPRT.

CR: JDK-8153578 Default NewRatio is ignored when UseConcMarkSweepGC is 
used as GC algorithm <https://bugs.openjdk.java.net/browse/JDK-8153578>

Webrev:  http://cr.openjdk.java.net/~jprovino/8153578/webrev.00