Bug 136246 [regression]Export data exported error column name.
Description: Export data exported error column name. Steps to reproduce: 1. export data in a table, select several columns. Expected result: Selected column name and data are exported. Actual result: No matter what columns you selected, exported columns name always display columns beginning from the first, and then the second, and so on.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/ReportEngineService.java
IScalarParameterDefn parameterObj = (IScalarParameterDefn) iter
					.next( );
			
			
			String parameterName = parameterObj.getName( );
			Object parameterValue = parameters.get( parameterName );
			if ( parameterObj.isHidden( ) )
			{
				continue;
			}
			if ( parameterValue == null && !parameterObj.allowNull( ) )
			{
				missingParameter = true;
				break;
			}
			if ( IScalarParameterDefn.TYPE_STRING == parameterObj.getDataType( ) )
			{
				String parameterStringValue = (String) parameterValue;
				if ( parameterStringValue != null
						&& parameterStringValue.length( ) <= 0
						&& !parameterObj.allowBlank( ) )
				{
					missingParameter = true;
					break;
				}
			}
		}
		return missingParameter;
	}
	/**