Added guard for OnTextBoxValueChanged so that it will not to set the data.Comment value when data == null. This failed on some build agents, although it could not be reproduced locally. However, this change prevents it from happening. Reviewed by: kleijn git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@3079 5a3db67b-de53-47b5-99c8-a1c30a6650e2