Bug 130094 [regression] cannot edit group in Cheat Sheets
steps to reproduce: - create a report using Grouped Listing template - switch to Cheat Sheets, start/restart the tutorial - follow the steps to 1) create data source; 2) create data set; 3) bind the data to the table; and 4) edit the group expected behavior: - group dialog should be displayed actual behavior: - error message displayed. please refer to the attached image for detail
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/views/DefaultNodeProvider.java
return DEUtil.getDisplayLabel( model );
	}
	/**
	 * Gets the children element of the given model using visitor.
	 * 
	 * @param model
	 *            the model
	 */
	public Object[] getChildren( Object model )
	{
		if ( model instanceof ReportElementModel )
		{
			if ( ( (ReportElementModel) model ).getSlotHandle( ) != null )
			{
				Object[] children = this.getChildrenBySlotHandle( ( (ReportElementModel) model ).getSlotHandle( ) );
				if ( comparator != null )
				{
					Arrays.sort( children, comparator );
				}
				return children;
			}
		}
		return new Object[]{};
	}
	public Object getParent( Object model )
	{
		if ( model instanceof ReportElementModel )
		{
			return ( (ReportElementModel) model ).getElementHandle( );
		}