Last commit did not pick up all the changes because MOE incorrectly attributed some changes to the wrong commit. This commit should reconcile these. Also picked up some changes to how hamcrest library is depended upon in BUILD file, which should have been included in previous commits.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177637931
This was a surprisingly involved change. Some of the difficulties included
java.util.Optional purposely not being Serializable (so I had to move a
few Optionals in mapreduce classes to @Nullable) and having to add the Truth
Java8 extension library for assertion support.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=171863777
This is to fix Kokoro, given the directory added in [] Also, added forgotten keyring/api directory.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=167598465