Fix OK statuses not being broadcasted during a sync #3944

Fix OK statuses not being broadcasted during a sync #3944

Since the presence of any path in SyncEngine::_syncedItems
would translate in a SYNC status, platforms that don't refresh
all their status cache after an UPDATE_VIEW message like OS X
or Windows would keep displaying that status even after all
files are successfully synchronized.

- Read SyncFileItem::_status to determine the status to display mid-sync
- Match moved paths also to _renameTarget since this might be the
  path to match
- Make sure that PropagateDirectory jobs also set SyncFileItem::_status
  properly