Summary: Ref T13242. See <https://discourse.phabricator-community.org/t/out-of-range-value-for-column-deviceversion/2218>. The synchronization log column is `uint32?` and `-1` doesn't go into that column. Since we're only using `-1` for convenience to cheat through `$max_version > $this_version` checks, use `null` instead and make the checks more explicit. Test Plan: Reproducing this is a bit tricky and I cheated fairly heavily to force the code down this pathway without actually building a multi-device cluster, but I did reproduce the original exception, apply the patch, and observe that it fixed things. Reviewers: amckinley Reviewed By: amckinley Maniphest Tasks: T13242 Differential Revision: https://secure.phabricator.com/D20047