mozilla-services/android-sync — comment on commit db2de0f8434be941663bbf5857bfbe7467200499
File: src/main/java/org/mozilla/gecko/sync/stage/SyncClientsEngineStage.java line 182
By rnewman:

One thing I've learned from Sync: be really explicit with this kind of thing.

```
long now = System.currentTimeMillis();
long lastUpload = session.getServerClientRecordTimestamp(); // Defaults to 0.
long age = now - lastUpload;
return age >= CLIENTS_TTL_REFRESH;
```