Bug 153523 OK button in parameter dialog is enabled without default value in combo-box
Description: OK button in parameter dialog is enabled without default value in combo-box Steps to reproduce: 1. New a report parameter, combo-box. 2. Click New button, input abc as value, click OK 3. Set abc as default value and close Edit Parameter dialog. 4. New a data source and dataset 5. Edit the parameter, remove abc value and import values from dataset Expected result: OK button is disabled for there is no default value. Actual result: OK button is enabled.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
public void dispose( )
		{
		}
		public boolean isLabelProperty( Object element, String property )
		{
			return false;
		}
		public void removeListener( ILabelProviderListener listener )
		{
		}
	};
	private ICellModifier cellModifier = new ICellModifier( ) {
		public boolean canModify( Object element, String property )
		{
			if ( element != selectedParameter || property.equals( COLUMN_NAME ) )
			{
				return false;
			}
			if ( COLUMN_DATA_SET.equals( property ) )
			{
				if ( isSingle( ) && getFirstParameter( ) != element )
				{
					return false;
				}
			}
			if ( element == newParameter )
			{
				if ( isSingle( ) )
				{
					if ( element == getFirstParameter( ) )