Try to find additional JLS compatibility tests

[dz333]

From @gharrma on March 14, 2018 4:5

There are plenty of Java compilers out there, so it should be possible to find open source test suites that we can use to augment our own. Unfortunately so far I've found only very out-of-date test suites.

Copied from original issue: gharrma/polyllvm#45

[dz333]

From @andrewcmyers on March 14, 2018 12:42

Chin used some large test suite whose name I don't remember right now to test Java compatibility.

[dz333]

From @andrewcmyers on March 14, 2018 20:41

It was the Jacks test suite, which has apparently been absorbed into Mauve. http://www.sourceware.org/mauve/