Bug 138828 Export data column are disordered
Steps to reproduce: 1.Add a sample data source and a data set with table "CUSTOMERS" 2.Preview in Web Viewer 3.Click "Export data", choose columns "CUSTOMERNAME","PHONE","CITY","STATE" to be exported, click "OK" Expected result: The exported columns is alphabetic order or the same order as selected columns Actual result: The exported columns is disordered. they are "STATE","CITY","CUSTOMERNAME","PHONE".
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/ReportEngineService.java
{
	private static ReportEngineService instance;
	/**
	 * Report engine instance.
	 */
	private IReportEngine engine = null;
	/**
	 * Static engine config instance.
	 */
	private EngineConfig config = null;
	/**
	 * Image directory for report images and charts.
	 */
	private String imageDirectory = null;
	/**
	 * URL accesses images.
	 */
	private String imageBaseUrl = null;
	/**
	 * Image handler instance.
	 */
	private HTMLServerImageHandler imageHandler = null;
	/**
	 * Web app context path.
	 */
	private String contextPath = null;