Fix test flakiness when running too fast because of time collision.
Fix test flakiness when running too fast because of time collision.

BUG=
R=chrisha@chromium.org

Review URL: https://codereview.chromium.org/1302233004 .

Eloston/syzygy,supriyantomaftuh/syzygy,google/syzygy,google/syzygy,google/syzygy,supriyantomaftuh/syzygy,Eloston/syzygy,supriyantomaftuh/syzygy,google/syzygy,supriyantomaftuh/syzygy