M52 branch builds fail at update hardware test stage


** Stage that runs tests in the Autotest lab.
************************************************************
23:20:01: INFO: Waiting up to forever for payloads ...
23:23:52: INFO: RunCommand: /b/cbuild/shared_internal/chromite/third_party/swarming.client/swarming.py run --swarming chromeos-proxy.appspot.com --task-summary-json /tmp/cbuildbot-tmpbJrp9s/cbuildbot-tmpEamdwe/tmpfsZvgm/temp_summary.json --raw-cmd --task-name auron_paine-release/R52-8350.32.0-sanity --dimension os Ubuntu-14.04 --dimension pool default --print-status-updates --timeout 39600 --io-timeout 39600 --hard-timeout 39600 --expiration 1200 -- /usr/local/autotest/site_utils/run_suite.py --build auron_paine-release/R52-8350.32.0 --board auron_paine --suite_name sanity --pool bvt --num 1 --file_bugs True --priority DEFAULT --timeout_mins 600 --retry True --max_retries 10 --suite_min_duts 1 --offload_failures_only False -c
Autotest instance: cautotest
06-15-2016 [23:23:57] Submitted create_suite_job rpc
06-15-2016 [23:24:18] Created suite job: http://cautotest.corp.google.com/afe/#tab_id=view_job&object_id=66921936
@@@STEP_LINK@Link to suite@http://cautotest.corp.google.com/afe/#tab_id=view_job&object_id=66921936@@@
--create_and_return was specified, terminating now.
Will return from run_suite with status: OK
23:24:20: INFO: RunCommand: /b/cbuild/shared_internal/chromite/third_party/swarming.client/swarming.py run --swarming chromeos-proxy.appspot.com --task-summary-json /tmp/cbuildbot-tmpbJrp9s/cbuildbot-tmpEamdwe/tmpgPm5MQ/temp_summary.json --raw-cmd --task-name auron_paine-release/R52-8350.32.0-sanity --dimension os Ubuntu-14.04 --dimension pool default --print-status-updates --timeout 39600 --io-timeout 39600 --hard-timeout 39600 --expiration 1200 -- /usr/local/autotest/site_utils/run_suite.py --build auron_paine-release/R52-8350.32.0 --board auron_paine --suite_name sanity --pool bvt --num 1 --file_bugs True --priority DEFAULT --timeout_mins 600 --retry True --max_retries 10 --suite_min_duts 1 --offload_failures_only False -m 66921936
23:38:09: ERROR: wait_cmd has lab failures: cwd=None.
Exception will be raised in the next json_dump run.
Autotest instance: cautotest
06-15-2016 [23:24:18] Created suite job: http://cautotest.corp.google.com/afe/#tab_id=view_job&object_id=66921936
@@@STEP_LINK@Link to suite@http://cautotest.corp.google.com/afe/#tab_id=view_job&object_id=66921936@@@
Suite job   [ PASSED ]
provision   [ FAILED ]
provision     FAIL: Failed to install device image using payload at http://100.107.160.7:8082/update/auron_paine-release/R52-8350.32.0 on chromeos4-row8-rack3-host4. Update failed. Returned update_engine error code: ERROR_CODE=37, ERROR_MESSAGE=ErrorCode::kOmahaErrorInHTTPResponse. Reported error: AutoservRunError

Link to build:
https://uberchromegw.corp.google.com/i/chromeos_release/builders/auron_paine-release%20release-R52-8350.B/builds/26

Link to build failure log:
https://uberchromegw.corp.google.com/i/chromeos_release/builders/auron_paine-release%20release-R52-8350.B/builds/26/steps/HWTest%20%5Bsanity%5D/logs/stdio

Link to test logs:
https://00e9e64bac805dfadef66f9dc0ffbe6517efb62bb7d46f7161-apidata.googleusercontent.com/download/storage/v1_internal/b/chromeos-autotest-results/o/66922003-chromeos-test%2Fchromeos4-row8-rack3-host4%2Fdebug%2Fautoserv.DEBUG?qk=AD5uMEsfgD4ggu6nAa1kKCyzBu78ZXiSOBJcoFV2M9TbU1ATorweaqzh8zAyEZlCdX9t-j7RW5ZeYoPokIeiP1XkqD-zxkqwryNTOH5vngAXo73_HOIEpSkL56ep8-TraRnSCSfcBtj-2QO8SbAJNMUJaqTkIpxHbrQ43lm43sKfLMTpwoIeh0AcSpldLqi6ORR6pY4hv9avuh_A7OXUf2mMyMmaA7IkE-XQ6_dFiM4D2wzbgp5D19bFlsDMslJdo_8o6DQBOs9dF06D5lsLQxOj0__Hl1h1jQ0-vLFz1JnAXXWA6kox5YwH1rLkWrieNmGbEcl3bAkz07LMCNvvJIuw8SKOFTVeSJAAjw5xNyqqp6ywG43-kAai6LoYZg7J4LbTTMZy00yWJwAagxHKmPqhktT2BONRu9hZHkq4YMn3NswlZHpyjlaIX4GqFB-sV5IofwHBY6H3lfJb8sSG7bryi6tKdUpH7l0YOsYZhUrdINOpwz7jiwzJzPi-opTBvbYvJGJpaH5YPF1LHVDPE4jnSNk03OeG4lcWKErm9Lry-C9hBWVVcfK2wzVB9XW_JGrIm3rsK4oWrVQt2ifIbr2cRXRcnLqiOUD2vVxx6s5wd1QdmgdunCpXyldwBwezveEYSJ-NwBnzR1PlqiLZunkPPfFbcQOD4yrXT9PSsjFMVur-1TqAOPF4-xr8BrlZftHR64VlpSTmXBRT04saVQ-UV4YorUzLGYtE8olNCcH4xl2gdXHtQ3oMqZsgWe-Hu4U7eD9fQyPYBvuFPLSGfwLidnOuJnVkaM1RN7I9g6fHTB2UTHTyG_hzW5ODpJlpciej-7q17tHnfzGg8wYaOlUaPUeetiZBcTBlrNKIY72QJN24bxPJBGWJ6XZzsq84P43VwURFEsIZGgE-33jx4ivm9JbIrY6aocAa4nSfFAgQVUCLrGWFcJc