Yes, they should be consistent. `n.getActiveFields` writes a single byte whose bits are defined in `NODE_FIELDS` and are 0 if the particular values are `null` or `size() == 0`.  The `setByCopy()` function might be a little more permissive in that if `size() == 0`, it will create a new list of length 0 rather than being `null`.  Shouldn't affect behavior but I could change it to be more consistent if we want.