Test failure in testMultipleLocalSchedulers.

[robertnishihara]

The test

python test/runtest.py ResourcesTest .testMultipleLocalSchedulers

sometimes fails. One example is here https://s3.amazonaws.com/archive.travis-ci.org/jobs/235769863/log.txt?X-Amz-Expires=30&X-Amz-Date=20170524T234705Z&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAJRYRXRSVGNKPKO5A/20170524/us-east-1/s3/aws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=9ecc5f83cdc5c40d0956165ebce4329ea5c46b9e905dd43c2e12888831d45136.

The following line is logged.

[WARN] (/Users/travis/build/ray-project/ray/src/common/state/table.cc:85) retrying operation db_client_table_remove, retry_count = -1

Then later I see the line

WARNING:root:Removed local_scheduler, client ID 302136da8609524123014356c92a329ec4e54c3a

[robertnishihara]

Closing because this may have been fixed by #789.