Filed by: dvarga [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=271789324&repo=autoland
Full log: https://queue.taskcluster.net/v1/task/FIgliYSJR5CYsHy62FOTnw/runs/0/artifacts/public/logs/live_backing.log

[task 2019-10-17T22:52:13.856Z] 22:52:13     INFO - TEST-START | /content-security-policy/generic/no-default-src.sub.html
[task 2019-10-17T22:52:13.856Z] 22:52:13     INFO - Closing window 74
[task 2019-10-17T22:56:14.042Z] 22:56:14     INFO - 
[task 2019-10-17T22:56:14.042Z] 22:56:14     INFO - TEST-PASS | /content-security-policy/generic/no-default-src.sub.html | Allows scripts from the same host. 
[task 2019-10-17T22:56:14.042Z] 22:56:14     INFO - TEST-UNEXPECTED-TIMEOUT | /content-security-policy/generic/no-default-src.sub.html | Violation report status OK. - Test timed out
[task 2019-10-17T22:56:14.480Z] 22:56:14     INFO - TEST-UNEXPECTED-TIMEOUT | /content-security-policy/generic/no-default-src.sub.html | expected OK
[task 2019-10-17T22:56:14.480Z] 22:56:14     INFO - TEST-INFO took 240624ms
[task 2019-10-17T22:56:14.918Z] 22:56:14     INFO - Closing logging queue
[task 2019-10-17T22:56:14.918Z] 22:56:14     INFO - queue closed
[task 2019-10-17T22:56:14.926Z] 22:56:14     INFO - Setting up ssl
[task 2019-10-17T22:56:14.946Z] 22:56:14     INFO - certutil | 
[task 2019-10-17T22:56:14.961Z] 22:56:14     INFO - certutil | 
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO - certutil | 
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO - Certificate Nickname                                         Trust Attributes
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO -                                                              SSL,S/MIME,JAR/XPI
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO - 
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO - web-platform-tests                                           CT,, 
[task 2019-10-17T22:56:14.977Z] 22:56:14     INFO - 
[task 2019-10-17T22:56:17.708Z] 22:56:17     INFO - adb Granting important runtime permissions to org.mozilla.geckoview.test
[task 2019-10-17T22:56:18.962Z] 22:56:18     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_DISABLE_NONLOCAL_CONNECTIONS=1 --es env8 R_LOG_DESTINATION=stderr --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 MOZ_CRASHREPORTER_SHUTDOWN=1 --es env6 MOZ_IN_AUTOMATION=1 --es env5 MOZ_LOG=signaling:3,mtransport:4,DataChannel:4,jsep:4 --es env4 STYLO_THREADS=4 --ez use_multiprocess True --es env12 R_LOG_LEVEL=6 --es env11 MOZ_PROCESS_LOG=/tmp/tmpdEAQ0epidlog --es env10 MOZ_CRASHREPORTER_NO_REPORT=1
[task 2019-10-17T22:56:20.346Z] 22:56:20     INFO - Starting runner

aryx
Spike in failures got fixed by backout of bug 1589461.

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=300631847&repo=try&lineNumber=2329

https://wiki.mozilla.org/Bug_Triage#Intermittent_Test_Failure_Cleanup
For more information, please visit auto_nag documentation.