Sites use single-character values to defeat our skipEmptyFields heuristic at capture time. It's probably not useful to save a single-character password as most sites wouldn't allow such a short password.

This should fix sites like citi.com which have many hidden password fields with static single-character passwords.

Test case: when submitting the form, we expect to get prompted to save a 12-character password with the username "actual-username".

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=7919a2de2db581ee9804a8c32c5cfe7486b31626
I'm not sure if that test will run & pass on Android. We'll find out.

Backed out changeset a1917a9966fb (bug 1543449) for Android failures at tests/SimpleTest/SimpleTest.js

Backout: https://hg.mozilla.org/integration/autoland/rev/9790d2e8f40b840c55d15b918162b040a2a92e0e

Failure push: https://treeherder.mozilla.org/#/jobs?repo=autoland&revision=a1917a9966fb544d1b4c172aa5acca7fa9bf5cae&selectedJob=240104549

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=240104549&repo=autoland&lineNumber=2357

[task 2019-04-13T04:36:51.585Z] 04:36:51 INFO - 388 INFO TEST-OK | toolkit/components/passwordmgr/test/mochitest/test_xhr_2.html | took 2475ms
[task 2019-04-13T04:36:51.586Z] 04:36:51 INFO - 389 INFO TEST-START | Shutdown
[task 2019-04-13T04:36:51.586Z] 04:36:51 INFO - 390 INFO Passed: 587
[task 2019-04-13T04:36:51.587Z] 04:36:51 INFO - 391 INFO Failed: 0
[task 2019-04-13T04:36:51.588Z] 04:36:51 INFO - 392 INFO Todo: 30
[task 2019-04-13T04:36:51.589Z] 04:36:51 INFO - 393 INFO Mode: non-e10s
[task 2019-04-13T04:36:51.589Z] 04:36:51 INFO - 394 INFO Slowest: 197723ms - /tests/toolkit/components/passwordmgr/test/mochitest/test_formless_submit_navigation_negative.html
[task 2019-04-13T04:36:51.589Z] 04:36:51 INFO - 395 INFO SimpleTest FINISHED
[task 2019-04-13T04:36:55.337Z] 04:36:55 INFO - wait for org.mozilla.fennec_aurora complete; top activity=com.android.launcher
[task 2019-04-13T04:36:55.544Z] 04:36:55 INFO - remoteautomation.py | Application ran for: 0:09:44.227681
[task 2019-04-13T04:36:59.606Z] 04:36:59 INFO - adb Ignoring attempt to chmod external storage
[task 2019-04-13T04:36:59.606Z] 04:36:59 INFO - runtests.py | Running with scheme: https
[task 2019-04-13T04:36:59.606Z] 04:36:59 INFO - runtests.py | Running with e10s: False
[task 2019-04-13T04:36:59.606Z] 04:36:59 INFO - runtests.py | Running with serviceworker_e10s: False
[task 2019-04-13T04:36:59.606Z] 04:36:59 INFO - runtests.py | Running with socketprocess_e10s: False
[task 2019-04-13T04:36:59.607Z] 04:36:59 INFO - runtests.py | Running tests: start.
[task 2019-04-13T04:36:59.923Z] 04:36:59 INFO - remoteautomation.py | runApp deleted /sdcard/tests/logs/mochitest.log
[task 2019-04-13T04:37:00.337Z] 04:37:00 INFO - adb launch_application: am start -W -n org.mozilla.fennec_aurora/org.mozilla.gecko.BrowserApp -a android.intent.action.VIEW --es env9 MOZ_CRASHREPORTER_NO_REPORT=1 --es env8 MOZ_UPLOAD_DIR=/sdcard/tests/mozlog --es args "-no-remote -profile /sdcard/tests/profile//" --es env3 DISABLE_UNSAFE_CPOW_WARNINGS=1 --es env2 R_LOG_VERBOSE=1 --es env1 XPCOM_DEBUG_BREAK=stack --es env0 MOZ_CRASHREPORTER=1 --es env7 R_LOG_DESTINATION=stderr --es env6 MOZ_CRASHREPORTER_SHUTDOWN=1 --es env5 MOZ_IN_AUTOMATION=1 --es env4 MOZ_DISABLE_NONLOCAL_CONNECTIONS=1 --es env11 MOZ_HIDE_RESULTS_TABLE=1 --es env10 R_LOG_LEVEL=6 -d "https://example.com:443/tests?autorun=1&closeWhenDone=1&logFile=%2Fsdcard%2Ftests%2Flogs%2Fmochitest.log&fileLevel=INFO&consoleLevel=INFO&hideResultsTable=1&manifestFile=tests.json&dumpOutputDirectory=%2Fsdcard%2Ftests"
[task 2019-04-13T04:37:11.572Z] 04:37:11 INFO - remoteautomation.py | Application pid: 3507
[task 2019-04-13T04:38:18.537Z] 04:38:18 INFO - 396 INFO SimpleTest START
[task 2019-04-13T04:38:18.537Z] 04:38:18 INFO - 397 INFO TEST-START | toolkit/components/passwordmgr/test/mochitest/test_password_length.html
[task 2019-04-13T04:38:28.751Z] 04:38:28 INFO - 398 INFO TEST-OK | toolkit/components/passwordmgr/test/mochitest/test_password_length.html | took 18509ms
[task 2019-04-13T04:38:28.751Z] 04:38:28 INFO - 399 INFO TEST-START | Shutdown
[task 2019-04-13T04:38:28.751Z] 04:38:28 INFO - 400 INFO Passed: 12
[task 2019-04-13T04:38:28.752Z] 04:38:28 INFO - 401 INFO Failed: 0
[task 2019-04-13T04:38:28.752Z] 04:38:28 INFO - 402 INFO Todo: 0
[task 2019-04-13T04:38:28.752Z] 04:38:28 INFO - 403 INFO Mode: non-e10s
[task 2019-04-13T04:38:28.752Z] 04:38:28 INFO - 404 INFO Slowest: 18490ms - /tests/toolkit/components/passwordmgr/test/mochitest/test_password_length.html
[task 2019-04-13T04:38:28.752Z] 04:38:28 INFO - 405 INFO SimpleTest FINISHED
[task 2019-04-13T04:38:34.015Z] 04:38:34 INFO - Failed to get top activity, retrying, once...
[task 2019-04-13T04:40:32.011Z] 04:40:32 INFO - 406 INFO TEST-UNEXPECTED-FAIL | unknown test url | uncaught exception - TypeError: SimpleTest.harnessParameters is undefined at SimpleTest_setTimeoutShim@https://example.com/tests/SimpleTest/SimpleTest.js:669:17
[task 2019-04-13T04:40:32.012Z] 04:40:32 INFO - add_task@https://example.com/tests/SimpleTest/AddTask.js:30:7
[task 2019-04-13T04:40:32.012Z] 04:40:32 INFO - @https://example.com/tests/toolkit/components/passwordmgr/test/mochitest/test_password_length.html:43:1
[task 2019-04-13T04:40:32.012Z] 04:40:32 INFO - simpletestOnerror@https://example.com/tests/SimpleTest/SimpleTest.js:1665:24
[task 2019-04-13T04:40:40.021Z] 04:40:40 INFO - 407 INFO TEST-UNEXPECTED-FAIL | | /tests/toolkit/components/passwordmgr/test/mochitest/test_password_length.html - finished in a non-clean fashion, probably because it didn't call SimpleTest.finish()
[task 2019-04-13T04:40:40.021Z] 04:40:40 INFO - {u'loaded_test_url': u'/tests/toolkit/components/passwordmgr/test/mochitest/test_password_length.html'}
[task 2019-04-13T04:40:40.022Z] 04:40:40 INFO - 408 INFO TEST-UNEXPECTED-ERROR | | Finished in 18169ms
[task 2019-04-13T04:40:40.022Z] 04:40:40 INFO - {u'runtime': 18169}
[task 2019-04-13T04:40:40.022Z] 04:40:40 INFO - TEST-INFO

Thanks for the backout :ccoroiu, I thought I had checked this against android but it looks like my try run only ran xpcshell tests so I missed this. The test is skipped for android in the latest push.

https://hg.mozilla.org/mozilla-central/rev/127dba490969

https://hg.mozilla.org/mozilla-central/rev/33f6d42d7fa9

Backed out changeset 33f6d42d7fa9 (bug 1543449) for turning 1272849 into perma

push that casued the backout: https://treeherder.mozilla.org/#/jobs?repo=mozilla-inbound&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel%2Crunning%2Cpending%2Crunnable&searchStr=browser-chrome&revision=e9be442c871e173a409f3b969f5bcea0e1ae4d71

failures: https://treeherder.mozilla.org/#/jobs?repo=mozilla-inbound&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel%2Crunning%2Cpending%2Crunnable&searchStr=os%2Cx%2C10.10%2Cshippable%2Copt%2Cmochitests%2Ctest-macosx64-shippable%2Fopt-mochitest-browser-chrome-e10s-3%2Cm%28bc3%29&revision=e9be442c871e173a409f3b969f5bcea0e1ae4d71&selectedJob=241611983

backout: https://hg.mozilla.org/integration/mozilla-inbound/rev/2f7d2b9798c226df217f96a5d9a9862798647792

https://hg.mozilla.org/mozilla-central/rev/2f7d2b9798c2

I have used the test case from comment 1:

• Affected (Nightly v68.0a1 from 2019-04-08):
  The password manager pop-up to save the credentials would not appear at all.

• Fixed (Nightly v68.0a1 from 2019-04-23):
  The password manager prompt to save password will appear for the "actual-username" username only.

I have also tested a different test case (https://bug1352544.bmoattachments.org/attachment.cgi?id=9050123):

• Affected (Nightly v68.0a1 from 2019-04-08):
  When attempting to save a random username and a 1-letter password, the password manager prompt would appear and allow you to save a 1-letter password.
• Fixed (Nightly v68.0a1 from 2019-04-23):
  When attempting to save a random username and a 1-letter password, the password manager prompt would NOT appear at all.

Does this test suffice to verify this bug? If not, please provide some extra steps to verify. Thanks!

That sounds great