RFR J8050281: New permission tests for JEP 140

[Amanda Jiang]

Hi All,

Could you please review following 2 new regression tests to be added for 
JEP140 (Limied doPrivileged).
New tests are added to perform permission tests for limited doprivileged 
with multiple threads , and basic API testing.

JDK Issue: https://bugs.openjdk.java.net/browse/JDK-8050281
webrev: http://cr.openjdk.java.net/~rhalade/8050281/webrev.00/

Thanks,
Amanda