Several boards failed with an error like:

  Reason: Tests failed.
  
   12-01-2017 [11:50:01] Output below this line is for buildbot consumption:
  @@@STEP_LINK@[Test-Logs]: audio_Microphone: retry_count: 2, FAIL: Fail to get selected input device.@http://cautotest-prod/tko/retrieve_logs.cgi?job=/results/159672956-chromeos-test/@@@
  @@@STEP_LINK@[Flake-Dashboard]: audio_Microphone@https://wmatrix.googleplex.com/retry_teststats/?days_back=30&tests=audio_Microphone@@@
  @@@STEP_LINK@[Test-History]: audio_Microphone@https://wmatrix.googleplex.com/unfiltered?hide_missing=True&tests=audio_Microphone@@@
  Will return from run_suite with status: ERROR

Examples:
https://uberchromegw.corp.google.com/i/chromeos/builders/kip-paladin/builds/3721
https://uberchromegw.corp.google.com/i/chromeos/builders/nyan_kitty-paladin/builds/3732
https://uberchromegw.corp.google.com/i/chromeos/builders/peppy-paladin/builds/17247