Revert "Fail more informatively when tests are affected by syncback race condition."
Revert "Fail more informatively when tests are affected by syncback race condition."

This reverts commit 2495171ea09ac48f08b8e1bf82b17041acb5fa5f.

Reason for rollback: causes IOError when you try to run the whole test suite.

PriviPK/privipk-sync-engine,jobscore/sync-engine,ErinCall/sync-engine,gale320/sync-engine,nylas/sync-engine,closeio/nylas,PriviPK/privipk-sync-engine,gale320/sync-engine,PriviPK/privipk-sync-engine,closeio/nylas,closeio/nylas,Eagles2F/sync-engine,nylas/sync-engine,ErinCall/sync-engine,ErinCall/sync-engine,gale320/sync-engine,closeio/nylas,jobscore/sync-engine,EthanBlackburn/sync-engine,EthanBlackburn/sync-engine,jobscore/sync-engine,jobscore/sync-engine,EthanBlackburn/sync-engine,nylas/sync-engine,wakermahmud/sync-engine,ErinCall/sync-engine,gale320/sync-engine,ErinCall/sync-engine,EthanBlackburn/sync-engine,wakermahmud/sync-engine,wakermahmud/sync-engine,Eagles2F/sync-engine,Eagles2F/sync-engine,PriviPK/privipk-sync-engine,EthanBlackburn/sync-engine,PriviPK/privipk-sync-engine,nylas/sync-engine,gale320/sync-engine,Eagles2F/sync-engine,wakermahmud/sync-engine,Eagles2F/sync-engine,wakermahmud/sync-engine