The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1

commit ca0df3b15c395d8b5ac01141cdbe4c18bec778c1
Author: lijeffrey <lijeffrey@chromium.org>
Date: Fri Aug 19 04:32:08 2016

[Findit] Display last build bucket response to try job dashboard

The UI now looks like this:
https://lijeffrey1-dot-findit-for-me.appspot.com/waterfall/try-job-dashboard?start_date=2016-08-15&end_date=2016-08-18

This CL also fixes a misleading error message when buildbucket reports an error.

BUG= 638690 ,  611866 

Review-Url: https://codereview.chromium.org/2259513003

[modify] https://crrev.com/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1/appengine/findit/handlers/test/try_job_dashboard_test.py
[modify] https://crrev.com/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1/appengine/findit/handlers/try_job_dashboard.py
[modify] https://crrev.com/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1/appengine/findit/templates/try_job_dashboard.html
[modify] https://crrev.com/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1/appengine/findit/waterfall/monitor_try_job_pipeline.py
[modify] https://crrev.com/ca0df3b15c395d8b5ac01141cdbe4c18bec778c1/appengine/findit/waterfall/test/monitor_try_job_pipeline_test.py