RFR: JDK-8024665 Move open changes for JDK-8020411 to closed source

[Magnus Ihse Bursie]

The fix for JDK-8020411 contains logic that is only needed for closed 
source. Also, the changes conflicts with the changes needed for 
JDK-8024265, and it also inadvertently removed code needed for later 
CFLAGS checking.

These changes should be moved to closed source.
Webrev (for open part):
http://cr.openjdk.java.net/~ihse/JDK-8024665-move-changes-from-JDK-8020411-to-closed/webrev.01

/Magnus