Fix db_universal_compaction_test
Fix db_universal_compaction_test

Summary:
db_universal_compaction_test is still failing because of
UniversalCompactionNumLevels/DBTestUniversalCompaction.UniversalCompactionSecondPathRatio/0

https://travis-ci.org/facebook/rocksdb/jobs/94949919

Use same approach to fix other tests to fix this test

Test Plan: Run ./db_universal_compaction_test on mac and make sure all the tests pass

Reviewers: kradhakrishnan, yhchiang, rven, anthony, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D51591

Andymic/rocksdb,norton/rocksdb,hobinyoon/rocksdb,bbiao/rocksdb,wat-ze-hex/rocksdb,wat-ze-hex/rocksdb,facebook/rocksdb,wenduo/rocksdb,ryneli/rocksdb,tsheasha/rocksdb,Andymic/rocksdb,wenduo/rocksdb,flabby/rocksdb,SunguckLee/RocksDB,wat-ze-hex/rocksdb,jalexanderqed/rocksdb,hobinyoon/rocksdb,facebook/rocksdb,facebook/rocksdb,OverlordQ/rocksdb,jalexanderqed/rocksdb,flabby/rocksdb,facebook/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,Andymic/rocksdb,bbiao/rocksdb,tsheasha/rocksdb,wenduo/rocksdb,OverlordQ/rocksdb,wenduo/rocksdb,vmx/rocksdb,hobinyoon/rocksdb,wenduo/rocksdb,vmx/rocksdb,OverlordQ/rocksdb,hobinyoon/rocksdb,Vaisman/rocksdb,Andymic/rocksdb,ryneli/rocksdb,tsheasha/rocksdb,jalexanderqed/rocksdb,hobinyoon/rocksdb,vmx/rocksdb,Vaisman/rocksdb,SunguckLee/RocksDB,flabby/rocksdb,Vaisman/rocksdb,norton/rocksdb,norton/rocksdb,OverlordQ/rocksdb,flabby/rocksdb,vmx/rocksdb,facebook/rocksdb,hobinyoon/rocksdb,jalexanderqed/rocksdb,ryneli/rocksdb,facebook/rocksdb,wat-ze-hex/rocksdb,wat-ze-hex/rocksdb,bbiao/rocksdb,ryneli/rocksdb,OverlordQ/rocksdb,jalexanderqed/rocksdb,tsheasha/rocksdb,SunguckLee/RocksDB,SunguckLee/RocksDB,Andymic/rocksdb,SunguckLee/RocksDB,hobinyoon/rocksdb,bbiao/rocksdb,hobinyoon/rocksdb,flabby/rocksdb,Vaisman/rocksdb,ryneli/rocksdb,Andymic/rocksdb,facebook/rocksdb,norton/rocksdb,SunguckLee/RocksDB,Vaisman/rocksdb,facebook/rocksdb,Vaisman/rocksdb,wat-ze-hex/rocksdb,jalexanderqed/rocksdb,tsheasha/rocksdb,tsheasha/rocksdb,norton/rocksdb,tsheasha/rocksdb,norton/rocksdb,wenduo/rocksdb,Vaisman/rocksdb,Andymic/rocksdb,flabby/rocksdb,SunguckLee/RocksDB,wat-ze-hex/rocksdb,vmx/rocksdb,flabby/rocksdb,norton/rocksdb,wat-ze-hex/rocksdb,vmx/rocksdb,vmx/rocksdb,bbiao/rocksdb,ryneli/rocksdb,ryneli/rocksdb,norton/rocksdb,bbiao/rocksdb,bbiao/rocksdb,Andymic/rocksdb,wenduo/rocksdb,tsheasha/rocksdb,wenduo/rocksdb,OverlordQ/rocksdb,bbiao/rocksdb,vmx/rocksdb,jalexanderqed/rocksdb