The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra/+/12df794329ae44dcbcb093ab7e4c2aacefd4868e

commit 12df794329ae44dcbcb093ab7e4c2aacefd4868e
Author: Sergiy Byelozyorov <sergiyb@chromium.org>
Date: Thu Apr 20 15:23:01 2017

Chromium Try Flakes: add more logging

Bug:  713693 
Change-Id: Ic38ed2dc17cfa63e4a28e44e92fb7ed23bb306fa
Reviewed-on: https://chromium-review.googlesource.com/483361
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>

[modify] https://crrev.com/12df794329ae44dcbcb093ab7e4c2aacefd4868e/appengine/chromium_try_flakes/status/cq_status.py
[modify] https://crrev.com/12df794329ae44dcbcb093ab7e4c2aacefd4868e/appengine/chromium_try_flakes/handlers/flake_issues.py

Turns out num_reported_flaky_runs field was larger than the total number of flake. Not sure what changed it, but since we didn't have the logging before, it's hard to say now. Based on http://chromium-try-flakes.appspot.com/all_flake_occurrences?key=ahVzfmNocm9taXVtLXRyeS1mbGFrZXNyHwsSBUZsYWtlIhRjb21waWxlICh3aXRoIHBhdGNoKQw&show_all=1, this flakes has never been reported, so I've manually set num_reported_flaky_runs to 0 in the Datastore editor.