Bug 182680 Use feature of new Aggregation framework of Data Engine.
DataEngine will implement new aggregation framework in 2.2.0RC0. After the implementation is finished Engine should go ahead to use new column bindings in definition of map/highlight.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
usingParameterValues( );
		
		String expr = parameter.getDefaultValue( );
		String dataType = parameter.getDataType( );
		if ( expr == null
				|| ( expr.length( ) == 0 && !DesignChoiceConstants.PARAM_TYPE_STRING
						.equals( dataType ) ) )
		{
			return null;
		}
		return convertToType( expr, dataType );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.engine.api.IGetParameterDefinitionTask#getSelectionChoice(java.lang.String)
	 */
	public Collection getSelectionList( String name )
	{
		usingParameterValues( );
		ReportDesignHandle report = (ReportDesignHandle) this.runnable
				.getDesignHandle( );
		ScalarParameterHandle parameter = (ScalarParameterHandle) report
				.findParameter( name );
		if ( parameter == null )
		{
			return Collections.EMPTY_LIST;
		}
		String selectionType = parameter.getValueType( );
		String dataType = parameter.getDataType( );