On startup when we read roots, we can check their parents and reparent them. We could measure this with telemetry too. Need to take care of Sync though.

Misparented roots are going to confuse the mirror, too, and I suspect they're causing bug 1471988. Stealing this bug. :-)

This patch fixes up user content roots that aren't children of the Places root. This patch also changes the Sync mirror to always prefer the local root structure when merging, since the roots on the server might be wrong.

Comment on attachment 8989032 [details] Reparent Places roots on startup and handle misparented roots in the Sync mirror. Marco Bonardo [::mak] has approved the revision. https://phabricator.services.mozilla.com/D1904

Pushed by kcambridge@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/ddb83501ed00 Reparent Places roots on startup and handle misparented roots in the Sync mirror. r=mak

Backout by csabou@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/18a6d392999f Backed out changeset ddb83501ed00 for xpcshell failures on test_current_from_v43. CLOSED TREE

Backed out for xpcshell failures on test_current_from_v43 Push with failures: https://treeherder.mozilla.org/#/jobs?repo=autoland&filter-resultStatus=testfailed&filter-resultStatus=busted&filter-resultStatus=exception&tochange=18a6d392999fb556fd429ce542f49fd5ffd3655f&filter-searchStr=xpc&fromchange=ddb83501ed00ac36bc2cdca537882328d2046394&selectedJob=186728164 Failure log: https://treeherder.mozilla.org/logviewer.html#?job_id=186728164&repo=autoland&lineNumber=2076 Backout link: https://hg.mozilla.org/integration/autoland/rev/18a6d392999fb556fd429ce542f49fd5ffd3655f [task 2018-07-05T22:54:53.189Z] INFO - Retrying tests that failed when run in parallel. [task 2018-07-05T22:54:53.206Z] INFO - TEST-START | toolkit/components/places/tests/migration/test_current_from_v43.js [task 2018-07-05T22:54:53.592Z] WARNING - TEST-UNEXPECTED-FAIL | toolkit/components/places/tests/migration/test_current_from_v43.js | xpcshell return code: 0 [task 2018-07-05T22:54:53.592Z] INFO - TEST-INFO took 386ms [task 2018-07-05T22:54:53.592Z] INFO - >>>>>>> [task 2018-07-05T22:54:53.594Z] INFO - (xpcshell/head.js) | test MAIN run_test pending (1) [task 2018-07-05T22:54:53.595Z] INFO - (xpcshell/head.js) | test run_next_test 0 pending (2) [task 2018-07-05T22:54:53.595Z] INFO - (xpcshell/head.js) | test MAIN run_test finished (2) [task 2018-07-05T22:54:53.596Z] INFO - running event loop [task 2018-07-05T22:54:53.596Z] INFO - "CONSOLE_MESSAGE: (info) No chrome package registered for chrome://branding/locale/brand.properties" [task 2018-07-05T22:54:53.597Z] INFO - toolkit/components/places/tests/migration/test_current_from_v43.js | Starting setup [task 2018-07-05T22:54:53.597Z] INFO - (xpcshell/head.js) | test setup pending (2) [task 2018-07-05T22:54:53.597Z] INFO - (xpcshell/head.js) | test run_next_test 0 finished (2)

Pushed by kcambridge@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/4d0ff7720f70 Reparent Places roots on startup and handle misparented roots in the Sync mirror. r=mak

Sorry about that, rebased and fixed the test. :-) https://treeherder.mozilla.org/#/jobs?repo=try&revision=2786dd656a68327ba6ea846e406b69803f1f4649