Bug 140538 Can't save by auto when it is preview after create the 2nd parameter
Details: Can't save by auto when it is preview after create the 2nd parameter Step: 1.New a report design. 2.Create the 1st parameter and preview. 3.Create the 2nd parameter and preview. Actual result: After step 2, it is ok. After step 3, if I have not press save button, it will not save by auto.
UI/org.eclipse.birt.report.designer.ui.preview/src/org/eclipse/birt/report/designer/ui/preview/editors/ReportPreviewFormPage.java
ReportDesignHandle handle = sessionHandle
						.openDesign(configFileName);
				Iterator it = handle.configVariablesIterator();
				while (it.hasNext()) {
					ConfigVariableHandle configVar = (ConfigVariableHandle) it
							.next();
					if (configVar != null && configVar.getName() != null) {
						configVars.put(configVar.getName(), configVar
								.getValue());
					}
				}
			}
		} catch (DesignFileException e) {
			
			e.printStackTrace();
		}
		return configVars;
	}
	public boolean isMissingParameter() {
		boolean missingParameter = false;
		ModuleHandle model = SessionHandleAdapter.getInstance()
				.getReportDesignHandle();
		HashMap params = (HashMap) this.getConfigVars();
		List parameters = model.getFlattenParameters();
		if (parameters != null) {
			for (int i = 0; i < parameters.size(); i++) {
				if (parameters.get(i) instanceof ScalarParameterHandle) {
					ScalarParameterHandle parameter = ((ScalarParameterHandle) parameters
							.get(i));
					if (parameter.isHidden()) {