Bug 126839 [DataBinding] IObservable refactoring
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/viewers/TreeViewerUpdatableTreeExtended.java
return getColumnText(element, 0);
		}
	}
	
	
	private HashMap columnInfos = new HashMap();
	
	private IDataBindingContext dataBindingContext;
	private final TreeViewerDescription treeViewerDescription;
	private final IChangeListener dummyListener = new IChangeListener() {
		public void handleChange(ChangeEvent changeEvent) {
		}
	};
	/**
	 * @param treeViewerDescription
	 * @param dataBindingContext 
	 */
	public TreeViewerUpdatableTreeExtended(
			TreeViewerDescription treeViewerDescription, IDataBindingContext dataBindingContext) {
		super(treeViewerDescription.getTreeViewer(), treeViewerDescription.getClassTypes());
		this.treeViewerDescription = treeViewerDescription;
		this.dataBindingContext=dataBindingContext;
		
		fillDescriptionDefaults(dataBindingContext);
		TreeViewer tableViewer = treeViewerDescription.getTreeViewer();
		
		
		tableViewer.setLabelProvider(new TreeLabelProvider());
		tableViewer.setCellModifier(treeViewerDescription.getCellModifier());
		int columnCount = getColumnCount();