Position update is not delegated to server after client layout computation

[tortmayr]

After the client layout cycle only the computed bounds are reported back to the server. The position is only updated in the client model and remains unset at server side.

This results in a flicker on server update (because the position has to be set again from the client)
and for "more costly" operations (in terms of server roundtrip) this results in a visual bug: