Filed by: egao [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=252746404&repo=try
Full log: https://queue.taskcluster.net/v1/task/Z2OBRxolT3mWBqE5sKI3Fg/runs/0/artifacts/public/logs/live_backing.log

Platform: macosx1014-mojave

Context:
04:48:15 INFO - TEST-START | layout/generic/test/test_plugin_focus.html
04:48:15 INFO - GECKO(2040) | 2019-06-21 04:48:15.397 firefox[2040:21574] -[NSTaggedPointerString enumerateKeysAndObjectsUsingBlock:]: unrecognized selector sent to instance 0xe5e5e5e5e5e5e5e5
04:48:15 INFO - GECKO(2040) | Exiting due to channel error.
04:48:15 INFO - GECKO(2040) | Exiting due to channel error.
04:48:15 INFO - GECKO(2040) | [Child 2042, Chrome_ChildThread] WARNING: pipe error: Broken pipe: file /builds/worker/workspace/build/src/ipc/chromium/src/chrome/common/ipc_channel_posix.cc, line 728
04:48:15 INFO - GECKO(2040) | Exiting due to channel error.
04:48:15 INFO - GECKO(2040) | Exiting due to channel error.
04:48:15 INFO - GECKO(2040) | Exiting due to channel error.
04:48:15 INFO - TEST-INFO | Main app process: exit 1
04:48:15 INFO - Buffered messages logged at 04:48:15
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Got plugin painted event from p1
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Got plugin painted event from p2
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event type
04:48:15 INFO - TEST-PASS | layout/generic/test/test_plugin_focus.html | Check event target
04:48:15 INFO - must wait for focus
04:48:15 INFO - Buffered messages finished
04:48:15 ERROR - TEST-UNEXPECTED-FAIL | layout/generic/test/test_plugin_focus.html | application terminated with exit code 1
04:48:15 INFO - runtests.py | Application ran for: 0:01:09.056374
04:48:15 INFO - zombiecheck | Reading PID log: /var/folders/c6/_0c9rgmd3mvb1nhg162jstrh000017/T/tmppSXz6ipidlog
04:48:15 INFO - ==> process 2040 launched child process 2041
04:48:15 INFO - ==> process 2040 launched child process 2042
04:48:15 INFO - ==> process 2040 launched child process 2043
04:48:15 INFO - ==> process 2040 launched child process 2044
04:48:15 INFO - ==> process 2040 launched child process 2045
04:48:15 INFO - ==> process 2040 launched child process 2046
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2041
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2042
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2043
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2044
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2045
04:48:15 INFO - zombiecheck | Checking for orphan process with PID: 2046
04:48:15 INFO - mozcrash Copy/paste: /Users/cltbld/tasks/task_1561090513/build/macosx64-minidump_stackwalk /var/folders/c6/_0c9rgmd3mvb1nhg162jstrh000017/T/tmpEYcBQR.mozrunner/minidumps/708F51F9-C4DB-4689-9EFC-3282025064F7.dmp /Users/cltbld/tasks/task_1561090513/build/symbols
04:48:23 INFO - mozcrash Saved minidump as /Users/cltbld/tasks/task_1561090513/build/blobber_upload_dir/708F51F9-C4DB-4689-9EFC-3282025064F7.dmp
04:48:23 INFO - mozcrash Saved app info as /Users/cltbld/tasks/task_1561090513/build/blobber_upload_dir/708F51F9-C4DB-4689-9EFC-3282025064F7.extra
04:48:23 INFO - PROCESS-CRASH | layout/generic/test/test_plugin_focus.html | application crashed [@ CrashReporter::TerminateHandler()]