Bug 112287 It's better to transfer to "new data source" dialog when creating a new data set without existing data source.
Description: It's better to transfer to "new data source" dialog automatically when creating a new data set without existing data source. Steps to reproduce: 1. There is no existing data source. 2. Create a new data set. 3. It pops up hint message, saying that "there is no data source". Actual result: it's better to transfer to "new data source" dialog box now and help users create a new data source.
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
if ( needClean )
			{
				
				itemHandle.getPropertyHandle( ReportItemHandle.PARAM_BINDINGS_PROP )
						.clearValue( );
				itemHandle.getPropertyHandle( ExtendedItemHandle.FILTER_PROP )
						.clearValue( );
				itemHandle.getColumnBindings( ).clearValue( );
			}
			if ( needAddBinding )
			{
				
				List columnList = generateComputedColumns( itemHandle );
				if ( columnList.size( ) > 0 )
				{
					for ( Iterator iter = columnList.iterator( ); iter.hasNext( ); )
					{
						DEUtil.addColumn( itemHandle,
								(ComputedColumn) iter.next( ),
								false );
					}
				}
			}
		}
		catch ( SemanticException e )
		{
			ChartWizard.showException( e.getLocalizedMessage( ) );
		}
	}
	/**