Bug 153412 Change parameter type will cause preview fail
Description: Change parameter type will cause preview fail Steps to reproduce: 1. New a report paramter, string, text-box, default value is abc. 2. Drag the parameter to Layout and preview. 3. Change the parameter's type to integer, list-box, add a value 1 4. Preview Expected result: No errors. Actual result: The value "abc" is invalid with the type "integer".
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/actionhandler/BirtCacheParameterActionHandler.java
import org.eclipse.birt.report.model.api.ScalarParameterHandle;
import org.eclipse.birt.report.model.api.SessionHandle;
import org.eclipse.birt.report.model.api.elements.DesignChoiceConstants;
import org.eclipse.birt.report.model.api.elements.structures.ConfigVariable;
import org.eclipse.birt.report.model.api.util.ParameterValidationUtil;
import org.eclipse.birt.report.service.api.IViewerReportService;
import org.eclipse.birt.report.soapengine.api.Data;
import org.eclipse.birt.report.soapengine.api.GetUpdatedObjectsResponse;
import org.eclipse.birt.report.soapengine.api.Operation;
import org.eclipse.birt.report.soapengine.api.Oprand;
import org.eclipse.birt.report.soapengine.api.Update;
import org.eclipse.birt.report.soapengine.api.UpdateData;
import org.eclipse.birt.report.utility.ParameterAccessor;
import com.ibm.icu.util.ULocale;
public class BirtCacheParameterActionHandler extends AbstractBaseActionHandler
{
	/**
	 * Constructor.
	 * 
	 * @param context
	 * @param operation
	 */
	public BirtCacheParameterActionHandler( IContext context,
			Operation operation, GetUpdatedObjectsResponse response )
	{
		super( context, operation, response );
	}
	protected void __execute( ) throws Exception
	{
		ViewerAttributeBean attrBean = (ViewerAttributeBean) context.getBean( );