Sync duplicated object id migration (3)

[AlexeyBarabash]

Resolves brave/brave-browser#8358
Resolves brave/brave-browser#9110

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Verified that these changes build without errors on
  • Android
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that these changes pass automated tests (unit, browser, security tests) on
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that all lint errors/warnings are resolved (npm run lint)
• Ran git rebase master (if needed).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.
• Request a security/privacy review as needed.
• Add appropriate QA labels (QA/Yes or QA/No) to include the closed issue in milestone
• Public documentation has been updated as necessary. For instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Custom-Headers
  • https://github.com/brave/brave-browser/wiki/Web-compatibility-issues-with-tracking-protection
  • https://github.com/brave/brave-browser/wiki/QA-Guide

Test Plan:

See brave/brave-browser#8358
Also see brave/brave-browser#9110

Reviewer Checklist:

• New files have MPL-2.0 license header.
• Request a security/privacy review as needed.
• Adequate test coverage exists to prevent regressions
• Verify test plan is specified in PR before merging to source

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on.
• All relevant documentation has been updated.

[bsclifton]

Reviewed changes - works great 😄 I added a check for the Sync feature flag and then added a unit test for this too

[AlexeyBarabash]

309ea38 LGTM

[bsclifton]

CI had a failure; deleted auto-created brave-browser branch, rebased this branch against master, and pushed 👍

[bsclifton]

CI passed on all platforms, except for Android. Seems there was a signing issue during create_dist:
https://ci.brave.com/job/brave-browser-build-pr/job/sync_dup_obj_id_migration3/9/execution/node/463/log/

[bsclifton]

Android is building fine, tests pass- there's just a problem with create_dist (and the Jenkins setup). This appears to be happening with other PRs. Should be good to merge! 👍

@iefremov this should fix some of the crashes you've seen reported, I believe 😄

[btlechowski]

LGTM

Verification passed on

Brave	1.9.15 Chromium: 81.0.4044.92 (Official Build) nightly (64-bit)
Revision	32921c79b6f01a0fb2deef0e1d45b42f96581051-refs/branch-heads/4044@{#883}
OS	Ubuntu 18.04 LTS

Verified test plan from #5139

Steps used for brave/brave-browser#8358

1. Install 1.3.118
2. Go to about:flags#brave-sync and enable sync
3. Create a sync chain
4. Go to brave://bookmarks/
5. Add a bookmark
6. Exit browser
7. Copy content of Fix desktop profiles which are crashing because of sync object id duplication brave-browser#8358 (comment) to Bookmarks file
8. Upgrade to 1.9.15

Reproduced the crash after upgrade to 1.7.90
Verified no crash after upgrade to 1.9.15

Test case - disabled sync

1. Install 1.3.118
2. Go to about:flags#brave-sync and enable sync
3. Create a sync chain
4. Go to brave://bookmarks/
5. Add a bookmark
6. Exit browser
7. Copy content of Fix desktop profiles which are crashing because of sync object id duplication brave-browser#8358 (comment) to Bookmarks file
8. Upgrade to 1.9.15
9. Run brave with flag --disable-sync

Verified no crash after upgrade to 1.9.15

Verified test plan from brave/brave-browser#9110

Reproduced the crash after upgrade to 1.7.90
Verified no crash after upgrade to 1.9.15
Verified no crash after upgrade to 1.9.15 with flag --disable-sync