Bug 145729 Column binding name is created inconsistently on chart
Steps to reproduce: 1.New a table binding with a data set "ds" 2.Add a chart "chart1" in table header 3.In chart dialog, check "use data set" and choose "ds", column bindings are generated automatically,and their names are the same as those in table 4.Add anthor chart "chart2", binding it in Property Editor->Binding Expected result: Column binding name for chart2 is the same as chart1 Actual result: Column binding name for chart2 is different from those for chart1, and error will happen when running the report with chart2
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
DataSetHandle dataSetHandle = handle.getDataSet( );
		if ( dataSetHandle == null )
		{
			dataSetHandle = DEUtil.getBindingHolder( handle ).getDataSet( );
		}
		if ( dataSetHandle != null )
		{
			List resultSetColumnList = DataUtil.getColumnList( dataSetHandle );
			ArrayList columnList = new ArrayList( );
			for ( Iterator iter = resultSetColumnList.iterator( ); iter.hasNext( ); )
			{
				ResultSetColumnHandle resultSetColumn = (ResultSetColumnHandle) iter.next( );
				ComputedColumn column = StructureFactory.createComputedColumn( );
				column.setName( resultSetColumn.getColumnName( ) );
				column.setDataType( resultSetColumn.getDataType( ) );
				column.setExpression( DEUtil.getExpression( resultSetColumn ) );
				columnList.add( column );
			}
			return columnList;
		}
		return Collections.EMPTY_LIST;
	}
	/**
	 * Gets dataset from ReportItemHandle at first. If null, get dataset from
	 * its container.
	 * 
	 * @return direct dataset
	 */
	protected DataSetHandle getDataSetFromHandle( )
	{