This try push shows a few more tests failing when we enable the new migration wizard by default: https://treeherder.mozilla.org/jobs?repo=try&revision=a744671bf83fb2cbb9eeeb1f196bc31037f64850

I didn't realize there'd be this many, so instead of doing one-off test fixes, I'm going to put some utilities into BrowserTestUtils to make this all easier.

Backed out for causing failures on browser_noLoginsView.js

• backout: https://hg.mozilla.org/integration/autoland/rev/80844c013e056073bfd61717d0de1efb7e53e1d7
• push: https://treeherder.mozilla.org/jobs?repo=autoland&group_state=expanded&revision=dcd7e55d1b56e2492f29feebe41c4b7f62309180
• failure log: https://treeherder.mozilla.org/logviewer?job_id=411270086&repo=autoland&lineNumber=10848

[task 2023-04-03T21:48:48.503Z] 21:48:48     INFO - Leaving test bound login_selected_when_login_added_and_in_no_logins_view
[task 2023-04-03T21:48:48.504Z] 21:48:48     INFO - Console message: SENTINEL
[task 2023-04-03T21:48:48.504Z] 21:48:48     INFO - Buffered messages finished
[task 2023-04-03T21:48:48.512Z] 21:48:48     INFO - TEST-UNEXPECTED-FAIL | browser/components/aboutlogins/tests/browser/browser_noLoginsView.js | A promise chain failed to handle a rejection: waitForCondition timer - Wait for migration wizard to open - still pending at the end of the test - stack: ensureDOMPromiseRejectionsProcessed@resource://testing-common/PromiseTestUtils.sys.mjs:115:17
[task 2023-04-03T21:48:48.513Z] 21:48:48     INFO - nextTest@chrome://mochikit/content/browser-test.js:674:29
[task 2023-04-03T21:48:48.513Z] 21:48:48     INFO - async*testScope/test_finish/<@chrome://mochikit/content/browser-test.js:1699:25
[task 2023-04-03T21:48:48.513Z] 21:48:48     INFO - run@chrome://mochikit/content/browser-test.js:1618:9
[task 2023-04-03T21:48:48.513Z] 21:48:48     INFO - Rejection date: Mon Apr 03 2023 21:48:48 GMT+0000 (Coordinated Universal Time) - false == true - {"filename":"resource://testing-common/PromiseTestUtils.sys.mjs","name":"assertNoUncaughtRejections","sourceId":556,"lineNumber":266,"columnNumber":14,"sourceLine":"","asyncCause":null,"asyncCaller":null,"caller":{"filename":"chrome://mochikit/content/browser-test.js","name":"nextTest","sourceId":519,"lineNumber":675,"columnNumber":29,"sourceLine":"","asyncCause":null,"asyncCaller":{"filename":"chrome://mochikit/content/browser-test.js","name":"testScope/test_finish/<","sourceId":519,"lineNumber":1699,"columnNumber":25,"sourceLine":"","asyncCause":null,"asyncCaller":null,"caller":{"filename":"chrome://mochikit/content/browser-test.js","name":"run","sourceId":519,"lineNumber":1618,"columnNumber":9,"sourceLine":"","asyncCause":null,"asyncCaller":null,"caller":null,"formattedStack":"run@chrome://mochikit/content/browser-test.js:1618:9\n","nativeSavedFrame":{}},"formattedStack":"async*testScope/test_finish/<@chrome://mochikit/content/browser-test.js:1699:25\nrun@chrome://mochikit/content/browser-test.js:1618:9\n","nativeSavedFrame":{}},"caller":null,"formattedStack":"nextTest@chrome://mochikit/content/browser-test.js:675:29\nasync*testScope/test_finish/<@chrome://mochikit/content/browser-test.js:1699:25\nrun@chrome://mochikit/content/browser-test.js:1618:9\n","nativeSavedFrame":{}},"formattedStack":"assertNoUncaughtRejections@resource://testing-common/PromiseTestUtils.sys.mjs:266:14\nnextTest@chrome://mochikit/content/browser-test.js:675:29\nasync*testScope/test_finish/<@chrome://mochikit/content/browser-test.js:1699:25\nrun@chrome://mochikit/content/browser-test.js:1618:9\n","nativeSavedFrame":{}}
[task 2023-04-03T21:48:48.514Z] 21:48:48     INFO - Stack trace:
[task 2023-04-03T21:48:48.514Z] 21:48:48     INFO - resource://testing-common/PromiseTestUtils.sys.mjs:assertNoUncaughtRejections:266
[task 2023-04-03T21:48:48.514Z] 21:48:48     INFO - chrome://mochikit/content/browser-test.js:nextTest:675
[task 2023-04-03T21:48:48.514Z] 21:48:48     INFO - chrome://mochikit/content/browser-test.js:testScope/test_finish/<:1699
[task 2023-04-03T21:48:48.514Z] 21:48:48     INFO - chrome://mochikit/content/browser-test.js:run:1618
[task 2023-04-03T21:48:48.515Z] 21:48:48     INFO - GECKO(6388) | JavaScript error: resource://testing-common/PromiseTestUtils.sys.mjs, line 115: uncaught exception: waitForCondition timer - Wait for migration wizard to open - still pending at the end of the test
[task 2023-04-03T21:48:48.516Z] 21:48:48     INFO - Console message: [JavaScript Error: "uncaught exception: waitForCondition timer - Wait for migration wizard to open - still pending at the end of the test" {file: "resource://testing-common/PromiseTestUtils.sys.mjs" line: 115}]
[task 2023-04-03T21:48:48.516Z] 21:48:48     INFO - GECKO(6388) | MEMORY STAT | vsize 11536MB | residentFast 464MB | heapAllocated 206MB
[task 2023-04-03T21:48:48.517Z] 21:48:48     INFO - TEST-OK | browser/components/aboutlogins/tests/browser/browser_noLoginsView.js | took 1189ms

Backed out for bc failure on browser_noLoginsView.js

Backout link: https://hg.mozilla.org/integration/autoland/rev/e07f2d9abaeb59e8c0188c6384787c69b5f3feae
Log link: https://treeherder.mozilla.org/logviewer?job_id=411375530&repo=autoland&lineNumber=2378

https://hg.mozilla.org/mozilla-central/rev/241fd60440ba