[Tracking Requested - why for this release]: Central as Beta sim: https://treeherder.mozilla.org/#/jobs?repo=try&revision=20a04997cec50341d5f8fc16b9d1a9e981c0c94f&filter-resultStatus=testfailed&filter-resultStatus=busted&filter-resultStatus=exception&filter-classifiedState=unclassified&selectedJob=188930687 Failure log: https://treeherder.mozilla.org/logviewer.html#?job_id=188930757&repo=try&lineNumber=2113 Log snippet: [task 2018-07-19T11:34:09.599Z] 11:34:09 INFO - TEST-START | xpcshell-e10s.ini:toolkit/components/extensions/test/xpcshell/test_ext_contentscript.js [task 2018-07-19T11:34:10.770Z] 11:34:10 INFO - TEST-PASS | xpcshell-e10s.ini:toolkit/components/extensions/test/xpcshell/test_ext_contentscript.js | took 1175ms [task 2018-07-19T11:34:10.791Z] 11:34:10 INFO - TEST-START | xpcshell-remote.ini:toolkit/components/extensions/test/xpcshell/test_ext_storage_idb_data_migration.js [task 2018-07-19T11:34:11.060Z] 11:34:11 WARNING - TEST-UNEXPECTED-FAIL | xpcshell-remote.ini:toolkit/components/extensions/test/xpcshell/test_ext_storage_idb_data_migration.js | xpcshell return code: 0 This is a regression from Bug 1475306.

I looked at the failure logs, and it is actually due to this error: ``` addons.manager ERROR startup failed: TypeError: Services.appinfo.version is undefined (resource://gre/modules/AddonManager.jsm:734:1) ``` (https://treeherder.mozilla.org/logviewer.html#?job_id=188930757&repo=try&lineNumber=2134) And so the issue is that in this test file we need to call AddonTestUtils.createAppInfo before importing ExtensionStorage.jsm, because it internally imports Services.jsm and it would make the following check to fail because Services.appinfo has been cached with an undefined version property when the test file runs on beta: ``` if (!MOZ_COMPATIBILITY_NIGHTLY) { PREF_EM_CHECK_COMPATIBILITY = PREF_EM_CHECK_COMPATIBILITY_BASE + "." + Services.appinfo.version.replace(BRANCH_REGEXP, "$1"); } ``` (https://searchfox.org/mozilla-central/rev/88199de427d3c5762b7f3c2a4860c10734abd867/toolkit/mozapps/extensions/AddonManager.jsm#732-735)

Comment on attachment 8993402 [details] Bug 1476929 - Fix test_ext_storage_idb_data_migration.js failure when running on beta. https://reviewboard.mozilla.org/r/258160/#review266322 add a commit message about why this change fixes the test.

Pushed by luca.greco@alcacoop.it: https://hg.mozilla.org/integration/autoland/rev/bf63176221f0 Fix test_ext_storage_idb_data_migration.js failure when running on beta. r=mixedpuppy

Verified fixed with yesterday's beta simulation: https://treeherder.mozilla.org/#/jobs?repo=try&revision=c71b2f6d020250736ae72f3b124b592f495a3708&filter-resultStatus=testfailed&filter-resultStatus=busted&filter-resultStatus=exception&filter-resultStatus=runnable&filter-resultStatus=retry&filter-resultStatus=usercancel