Bug 190207 Integrate Aggregation builder with charts
Charts should be able to use aggregates in their databinding definition. The UI is missing the "Add Aggregation..." button in the chart databinding dialog.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ColumnBindingDialog.java
.getStructure( ComputedColumn.COMPUTED_COLUMN_STRUCT )
			.getMember( ComputedColumn.DATA_TYPE_MEMBER )
			.getAllowedChoices( );
	private static final IChoice[] dataTypes = DATA_TYPE_CHOICE_SET.getChoices( null );
	private static final String[] dataTypeDisplayNames = ChoiceSetFactory.getDisplayNamefromChoiceSet( DATA_TYPE_CHOICE_SET );
	private boolean canSelect = false;
	protected ReportItemHandle inputElement;
	
	
	private TableViewer bindingTable;
	private ExpressionCellEditor expressionCellEditor;
	private String selectedColumnName = null;
	private String NullChoice = null;
	private int selectIndex;
	private IStructuredContentProvider contentProvider = new IStructuredContentProvider( ) {
		public void dispose( )
		{
		}
		public void inputChanged( Viewer viewer, Object oldInput,
				Object newInput )
		{
		}
		public Object[] getElements( Object inputElement )
		{
			List elementsList = getBindingList( (DesignElementHandle) inputElement );
			
			return elementsList.toArray( );
		}
	};
	private ITableLabelProvider labelProvider = new ITableLabelProvider( ) {