Filed by: aciure [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=257746874&repo=autoland
Full log: https://queue.taskcluster.net/v1/task/K6va_MncRGGEoC3gTk7OrA/runs/0/artifacts/public/logs/live_backing.log

[task 2019-07-22T23:15:57.123Z] 23:15:57 INFO - TEST-START | /fetch/corb/script-resource-with-json-parser-breaker.tentative.sub.html
[task 2019-07-22T23:15:57.139Z] 23:15:57 INFO - Closing window 2147483672
[task 2019-07-22T23:15:57.856Z] 23:15:57 INFO - TEST-UNEXPECTED-OK | /fetch/corb/script-resource-with-json-parser-breaker.tentative.sub.html | expected ERROR
[task 2019-07-22T23:15:57.856Z] 23:15:57 INFO - TEST-INFO expected ERROR | took 733ms
[task 2019-07-22T23:15:58.620Z] 23:15:58 INFO - Closing logging queue
[task 2019-07-22T23:15:58.620Z] 23:15:58 INFO - queue closed
[task 2019-07-22T23:15:58.630Z] 23:15:58 INFO - Setting up ssl
[task 2019-07-22T23:15:58.650Z] 23:15:58 INFO - certutil |
[task 2019-07-22T23:15:58.671Z] 23:15:58 INFO - certutil |
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO - certutil |
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO - Certificate Nickname Trust Attributes
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO - SSL,S/MIME,JAR/XPI
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO -
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO - web-platform-tests CT,,
[task 2019-07-22T23:15:58.687Z] 23:15:58 INFO -
[task 2019-07-22T23:16:00.439Z] 23:16:00 INFO - adb Granting important runtime permissions to org.mozilla.geckoview.test
[task 2019-07-22T23:16:01.994Z] 23:16:01 INFO - adb launch_application: am start -W -n org.mozilla.geckoview.test/org.mozilla.geckoview.test.TestRunnerActivity -a android.intent.action.MAIN --es env9 MOZ_CRASHREPORTER_NO_REPORT=1 --es env8 MOZ_DISABLE_NONLOCAL_CONNECTIONS=1 --es args "-no-remote -profile /sdcard/tests/profile --marionette about:blank" --es env3 MOZ_HIDE_RESULTS_TABLE=1 --es env2 R_LOG_VERBOSE=1 --es env1 MOZ_WEBRENDER=0 --es env0 MOZ_CRASHREPORTER=1 --es env7 R_LOG_DESTINATION=stderr --es env6 MOZ_CRASHREPORTER_SHUTDOWN=1 --es env5 MOZ_LOG=signaling:3,mtransport:4,DataChannel:4,jsep:4 --es env4 STYLO_THREADS=4 --ez use_multiprocess True --es env11 R_LOG_LEVEL=6 --es env10 MOZ_PROCESS_LOG=/tmp/tmpEKY6OVpidlog
[task 2019-07-22T23:16:03.156Z] 23:16:03 INFO - Starting runner

There is an intermittent failure in wptrunner that causes these failures. My patch on bug 1612831 will make it go away. But then we will end-up with failures like bug 1664426, which seem to be related to a broken test or a missing feature parity in Firefox.

There wasn't such a failure for about a year but given that the harness no longer errors out, i'm going to mark this bug as fixed.