[Bug] Deleted bookmarks are synced back from a 3rd un-synced device

[sv-ohorvath]

Steps to reproduce

1. Login on desktop, and 2 mobile devices on Fenix.
2. Sync a list of bookmarks.
3. Disable the bookmarks sync in Sync settings. Sync, so the setting takes effect on all 3 devices.
4. Delete some bookmarks on desktop.
5. Re-enable bookmarks sync. Trigger a sync.
6. Sync manually on one of the 2 mobile devices.
7. Leave the 2nd device on stand-by so it doesn't trigger an automatic sync.
8. After the bookmarks are removed from device Setup basic CI infrastructure #1 and desktop, sync device 🤖 Basic CI setup #2.

Expected behavior

Bookmarks are removed from device #2 as well.

Actual behavior

Bookmarks are not removed on device #2, but re-added on the other devices instead.

Device information

• Android device: Pixel 3 (Android 9), Nexus 9 (Android 7)
• Fenix version: 2.2.0-rc2, desktop Nightly 71.0a1

┆Issue is synchronized with this Jira Task

[stale]

See: #17373 This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.