[13] RFR 8228668: compiler/codegen/aes/TestAESMain.java failed with GCM mode must be used with NoPadding

[Valerie Peng]

Any one can help review this? It's for updating a hotspot regression 
test to use NoPadding when using AES GCM mode.

The regression test started failing after JDK8180392 "SunJCE provider 
should throw exceptions for unsupported mode and padding combinations" 
is integrated. Also removed some dead code in the other regression test.

Bug: https://bugs.openjdk.java.net/browse/JDK-8228668

Webrev: http://cr.openjdk.java.net/~valeriep/8228668/webrev.00/

Thanks,
Valerie