Filed by: egao [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=265783734&repo=try
Full log: https://queue.taskcluster.net/v1/task/BYyKzFi0S3KD1vm2UVVPcA/runs/0/artifacts/public/logs/live_backing.log

Platform: debian 10
Suite: mochitest-e10s
Chunk: 1

Context:
[task 2019-09-09T20:47:12.281Z] 20:47:12 INFO - TEST-PASS | browser/extensions/formautofill/test/mochitest/creditCard/test_clear_form.html | A valid string reason is expected
[task 2019-09-09T20:47:12.282Z] 20:47:12 INFO - TEST-PASS | browser/extensions/formautofill/test/mochitest/creditCard/test_clear_form.html | Reason cannot be empty
[task 2019-09-09T20:47:12.282Z] 20:47:12 INFO - TEST-FAIL | browser/extensions/formautofill/test/mochitest/creditCard/test_clear_form.html | The author of the test has indicated that flaky timeouts are expected. Reason: Guarantee asynchronous identifyAutofillFields is invoked
[task 2019-09-09T20:47:12.282Z] 20:47:12 INFO - expecting a popup
[task 2019-09-09T20:47:12.282Z] 20:47:12 INFO - popup shown for test
[task 2019-09-09T20:47:12.283Z] 20:47:12 INFO - popup shown for test
[task 2019-09-09T20:47:12.283Z] 20:47:12 INFO - popup shown for test
[task 2019-09-09T20:47:12.283Z] 20:47:12 INFO - popup shown for test
[task 2019-09-09T20:47:12.284Z] 20:47:12 INFO - Buffered messages finished
[task 2019-09-09T20:47:12.284Z] 20:47:12 INFO - TEST-UNEXPECTED-FAIL | browser/extensions/formautofill/test/mochitest/creditCard/test_clear_form.html | Test timed out.
[task 2019-09-09T20:47:12.284Z] 20:47:12 INFO - SimpleTest.ok@https://example.com/tests/SimpleTest/SimpleTest.js:277:18
[task 2019-09-09T20:47:12.284Z] 20:47:12 INFO - reportError@https://example.com/tests/SimpleTest/TestRunner.js:121:22
[task 2019-09-09T20:47:12.285Z] 20:47:12 INFO - TestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:142:18
[task 2019-09-09T20:47:12.285Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.285Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.285Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.285Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.286Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.286Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.286Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.286Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.286Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - setTimeout handlerTestRunner._checkForHangs@https://example.com/tests/SimpleTest/TestRunner.js:170:15
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - TestRunner.runTests/<@https://example.com/tests/SimpleTest/TestRunner.js:388:20
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - promise callbackTestRunner.runTests@https://example.com/tests/SimpleTest/TestRunner.js:375:50
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - RunSet.runtests@https://example.com/tests/SimpleTest/setup.js:201:14
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - RunSet.runall@https://example.com/tests/SimpleTest/setup.js:180:12
[task 2019-09-09T20:47:12.287Z] 20:47:12 INFO - hookupTests@https://example.com/tests/SimpleTest/setup.js:273:12
[task 2019-09-09T20:47:12.288Z] 20:47:12 INFO - parseTestManifest@https://example.com/manifestLibrary.js:48:13
[task 2019-09-09T20:47:12.288Z] 20:47:12 INFO - getTestManifest/req.onload@https://example.com/manifestLibrary.js:61:28
[task 2019-09-09T20:47:12.288Z] 20:47:12 INFO - EventHandlerNonNullgetTestManifest@https://example.com/manifestLibrary.js:57:3
[task 2019-09-09T20:47:12.288Z] 20:47:12 INFO - hookup@https://example.com/tests/SimpleTest/setup.js:253:20
[task 2019-09-09T20:47:12.288Z] 20:47:12 INFO - EventHandlerNonNull@https://example.com/tests?autorun=1&closeWhenDone=1&consoleLevel=INFO&manifestFile=tests.json&dumpOutputDirectory=%2Ftmp&cleanupCrashes=true:11:1
[task 2019-09-09T20:47:13.267Z] 20:47:13 INFO - expecting the storage cleanup
[task 2019-09-09T20:47:13.289Z] 20:47:13 INFO - GECKO(2313) | MEMORY STAT | vsize 2384MB | residentFast 143MB | heapAllocated 19MB
[task 2019-09-09T20:47:13.292Z] 20:47:13 INFO - TEST-OK | browser/extensions/formautofill/test/mochitest/creditCard/test_clear_form.html | took 323720ms

Like other related bugs in the autofill tests, this bug has been resolved with bug 1596526. For an explanation, please see bug 1596526 or bug 1580044.