mozilla-services/android-sync — comment on commit 6fd7b951af8140c7bd45728e9cdaeca7f5424ef0
File: src/main/java/org/mozilla/gecko/sync/stage/SyncClientsEngineStage.java line 153
By marina-samuel:

This would cause an issue on first upload when the server's timestamp is -1. Might be better to return null if it's the first upload:

```
Long timestamp = session.config.getPersistedServerClientRecordTimestamp() / 1000;
if (timestamp == 0) {
return null;
}
return Long.toString(timestamp);
```