Fix java 8 compilation failure.

Type inference changes prevent this code from compiling in java 8. In general,
methods that declare type parameters without using them in any formal parameter
declarations should be avoided.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=69903864
Fix a minor style guide violation.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=70269830
Upgrade Truth to 0.22
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=70679145
Migrate usages of Truth's Subject.is(Object) to isEqualTo(Object). The former is being removed.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72403024
Update Truth package name to the new location.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72403557
Migrate from Truth.ASSERT to Truth.assert_ or Truth.assertThat.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72563991
Attempt to fix up some test flakiness.

- Greatly increase timeout on PollingWatchService tests. The timeout shouldn't matter unless something's terribly wrong, so it should be ok to make it long.
- Try to ensure that asynchronous close tests for JimfsFileChannel are working as expected by being more careful in ensuring that all threads start blocking properly. Also switch to using Truth instead of assertTrue so that we'll get error messages that are actually helpful if the tests still fail.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72748113
Rename helper methods named "assertThat" in AbstractJimfsIntegrationTest to "assertThatPath" so that we can static import Truth.assertThat for normal Truth assertions instead of using assert_().that.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72751369
Add assertThat(Comparable) overload for custom comparable types.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73145243
Migrate usages of:
-MapSubject.hasKey(key).withValue(value) to MapSubject.containsEntry(key, value)
-MapSubject.hasKey(key) to MapSubject.containsKey(key)
-MapSubject.lacksKey(key) to MapSubject.doesNotContainKey(key)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73223123
Misc changes to FileTree.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73318805
Fix another case in PollingWatchServiceTest where it's possible to see either one or two events depending on when exactly a poll occurs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73325083
Reduce visibility of Subject.isNotA()
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74309082
Migrate users off of deprecated (or soon to be deprecated) Truth APIs.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74628842
Migrate off of deprecated Truth methods
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78584467
Clean up usages of deprecated Truth has() Collection methods:
-has().item(...) -> contains(...)
-has().allOf(...) -> containsAllOf(...)
-has().exactly(...) -> containsExactly(...)
-has().exactlyAs(...) -> containsExactlyElementsIn(...)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78681455
Migrate from Truth's deprecated iteratesAs(...) to containsExactly(...).inOrder().
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78848947
Update Truth version to 0.24.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79281813