The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra/+/5d06952ff2933024581c1b7a14ec0aa56cf5975b

commit 5d06952ff2933024581c1b7a14ec0aa56cf5975b
Author: Chan <chanli@chromium.org>
Date: Tue Feb 21 18:35:20 2017

[Findit] Flake Analyzer: Automatically determine iterations to run for a flake analysis.

For the first build, if the swarming rerun returns stable result, rerun the same build
using a higher number of iterations.

If all swarming reruns(with different number of iterations) for the first build all stable,
Bail out.

BUG= 669612 ,  681714 

Change-Id: I3fe1abeae43778c9bcab4da8a86ffeb6f36fd87d
Reviewed-on: https://chromium-review.googlesource.com/444823
Commit-Queue: Chan Li <chanli@chromium.org>
Reviewed-by: Roberto Carrillo <robertocn@chromium.org>
Reviewed-by: Jeffrey Li <lijeffrey@chromium.org>

[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/test/waterfall_config_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/trigger_base_swarming_task_pipeline.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/test/lookback_algorithm_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/recursive_flake_pipeline.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/lookback_algorithm.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/model/flake/test/flake_swarming_task_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/test/recursive_flake_pipeline_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/model/flake/master_flake_analysis.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/recursive_flake_try_job_pipeline.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/model/flake/flake_swarming_task.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/schedule_flake_try_job_pipeline.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/test/trigger_flake_swarming_task_pipeline_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/test/schedule_flake_try_job_pipeline_test.py
[modify] https://crrev.com/5d06952ff2933024581c1b7a14ec0aa56cf5975b/appengine/findit/waterfall/flake/test/recursive_flake_try_job_pipeline_test.py