RFR (XXS): JDK-8140539: compiler/membars/DekkerTest.java fails with -XX:CICompilerCount=1

[gerard ziemski]

hi all,

Please review this XXS follow-up fix to my recent fix to https://bugs.openjdk.java.net/browse/JDK-8129855. For the 
check-in I did not regenerate the commit patch, so it was missing the last 2 changes that I made.

This fix touches 2 files, adding back the last changes, that did not make it in:

#1 We fix comments in IgnoreUnrecognizedVMOptions.java as per Dan's last review
#2 We add back -XX:+IgnoreUnrecognizedVMOptions to Dekker.java test, which at one point, I thought we did not need it 
anymore.


References:
      bugid: https://bugs.openjdk.java.net/browse/JDK-8140539
     webrev: http://cr.openjdk.java.net/~gziemski/8140539_rev0


cheers