Merged revision(s) 460 from trunk/test/Common/DelftTools.Tests: fixing unit-tests by implementing IObservable interface for test-content-objects for TreeView Related to Issue WTI-75 ........ Related to Issue [WTI-92]git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/branches/0.5.0.0461@504 5a3db67b-de53-47b5-99c8-a1c30a6650e2Former-commit-id: 89418c9b33132f3ebd47f1a35d0b9dd7a3282c06