Preserve order when exporting bookmarks

[darkdh]

Test Plan:

1. Import a lot of bookmarks.
2. Export bookmarks to a file. (file A)
3. Delete all the bookmarks
4. Import from file A
5. The bookmarks order should be the same as step 1

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fix #7189

Auditors: @bbondy, @NejcZdovc

• 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).
• Ran git rebase -i to squash commits (if needed).

[bbondy]

++