RFR(XXS) : 8158754 : compilercontrol tests: RandomCommandsTest.java and RandomValidCommandsTest.java - fail in PIT

[Igor Ignatyev]

http://cr.openjdk.java.net/~iignatyev/8158754/webrev.00/
> 1 line changed: 1 ins; 0 del; 0 mod; 

Hi all,

could you please review this tiny fix for two compiler control tests? the tests spawn a new jvm and pass CompilerDirectivesLimit flag which is diagnostic, but don’t pass -XX:+UnlockDiagnosticVMOptions. so the tests fail on product builds. the fix simply adds -XX:+UnlockDiagnosticVMOptions.

tested: locally on macos using both product and fastdebug builds
JBS: https://bugs.openjdk.java.net/browse/JDK-8158754
webrev: http://cr.openjdk.java.net/~iignatyev/8158754/webrev.00/

Thanks,
— Igor