Another example:
https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVy5gELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCKvAWNocm9taXVtLm1hYy9NYWMxMC4xMiBUZXN0cy8zODI5L2Jyb3dzZXJfc2lkZV9uYXZpZ2F0aW9uX2NvbnRlbnRfYnJvd3NlcnRlc3RzIG9uIE1hYy0xMC4xMi9WMlZpVW5SalIyVjBWWE5sY2sxbFpHbGhRbkp2ZDNObGNsUmxjM1F1UVhWa2FXOUpia2xHY21GdFpVRnVaRU5zYjNObFNXNVRkV05qWlhOelEyST0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA

Logs:
https://pantheon.corp.google.com/logs/viewer?project=findit-for-me&_ga=1.96030428.118927748.1494873512&minLogLevel=0&expandAll=false&resource=gae_app%2Fmodule_id%2Fwaterfall-backend%2Fversion_id%2F11190-b44768f&logName=projects%2Ffindit-for-me%2Flogs%2Fappengine.googleapis.com%252Frequest_log&filters=text:%22WebRtcGetUserMediaBrowserTest.AudioInIFrameAndCloseInSuccessCb%22&timestamp=2017-08-15T02:50:20.542892000Z

The problem is at UpdateFlakeAnalysisDataPointsPipeline/_CreateDataPoint.

I suspect this happens if the swarming task ended in error.

756173 is the metabug for stabilizing the flake analyzer.

my bad!

The root cause is failure to pull build info from buildbot/milo, not the flake swarming task ending in error

Right -- Is there any correlation there? Can we still use the swarming results without the build info?

We need commit position/revision etc which AFAIK isn't available from swarming

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra/+/8f46ca82b668e753ffbb2d574bbdc80d2aefc07b

commit 8f46ca82b668e753ffbb2d574bbdc80d2aefc07b
Author: Jeffrey Li <lijeffrey@chromium.org>
Date: Tue Aug 22 23:03:23 2017

[Findit] Flake Analyzer - Add retry for getting build info

Bug:  756274 
Change-Id: I507a40e8c2cad6363b2b83f87e559a0f65fdfa26
Reviewed-on: https://chromium-review.googlesource.com/627381
Reviewed-by: Shuotao Gao <stgao@chromium.org>
Commit-Queue: Shuotao Gao <stgao@chromium.org>

[modify] https://crrev.com/8f46ca82b668e753ffbb2d574bbdc80d2aefc07b/appengine/findit/waterfall/flake/update_flake_analysis_data_points_pipeline.py
[modify] https://crrev.com/8f46ca82b668e753ffbb2d574bbdc80d2aefc07b/appengine/findit/waterfall/flake/test/update_flake_analysis_data_points_pipeline_test.py