RFR(S) : 8038756 : new WB API :: get/setVMFlag

[Igor Ignatyev]

Hi all,

Please review the patch which introduces new WhiteBox methods to get and 
set VM flags.

webrev: http://cr.openjdk.java.net/~iignatyev/8038756/webrev.00/
jbs: https://bugs.openjdk.java.net/browse/JDK-8038756
testing: jprt
-- 
Igor