Bug 135465 [smoke]An error occurred when new a casading Parameter
Description: An error occurred when new a casading Parameter Step to reproduce: 1.new a sample db data source and data set 2.New a cascading parameter group, named "gp1", 3.select the data set, then create two cascading parameters, one is row["customernumber"], named p1; the other is row["customername"] Actual result; error message occurred repeatly
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
if ( element != selectedParameter )
			{
				return false;
			}
			if ( element == newParameter )
			{
				if ( !property.equals( COLUMN_VALUE ) )
				{
					return false;
				}
			}
			else if ( property.equals( COLUMN_NAME ) )
			{
				return false;
			}
			if ( property.equals( COLUMN_VALUE ) )
			{
				if ( getDataSetColumns( (ScalarParameterHandle) element ).length == 0 )
				{
					return false;
				}
			}
			setCellEditorItems( );
			return true;
		}
		public Object getValue( Object element, String property )
		{
			if ( element instanceof ScalarParameterHandle )
			{
				ScalarParameterHandle parameter = (ScalarParameterHandle) element;