I observed this while authoring https://codereview.chromium.org/2581533002/ and seem to recall it addresses the issue. Will double check and resolve if fixed (upon landing).
Weirdly, I'm not able to reproduce this flakiness after 1000 iterations, with or without my CL from comment 3. Will leave this open for now - perhaps it was fixed elsewhere.
Comment 1 by bugdroid1@chromium.org
, Jan 6 2017