Fix travis build with test isolation
Fix travis build with test isolation

Since we seem to be experiencing weird interference between tests on Travis,
run every test in its own JVM until we find a better solution.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=228738848

google/nomulus,google/nomulus,google/nomulus,google/nomulus,google/nomulus,google/nomulus