Bug 153038 NPE when delete master page content in old report design.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/editors/schematic/editparts/ListEditPart.java
package org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts;
import java.util.List;
import org.eclipse.birt.report.designer.core.model.schematic.ListHandleAdapter;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.border.BaseBorder;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.border.SectionBorder;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.editpolicies.ListLayoutEditPolicy;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.editpolicies.ReportComponentEditPolicy;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.editpolicies.ReportContainerEditPolicy;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.figures.ListFigure;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.handles.AbstractGuideHandle;
import org.eclipse.birt.report.designer.internal.ui.editors.schematic.handles.TableGuideHandle;
import org.eclipse.birt.report.designer.internal.ui.util.ExceptionHandler;
import org.eclipse.birt.report.designer.internal.ui.util.UIUtil;
import org.eclipse.birt.report.designer.nls.Messages;
import org.eclipse.birt.report.designer.ui.IReportGraphicConstants;
import org.eclipse.birt.report.designer.ui.ReportPlatformUIImages;
import org.eclipse.birt.report.designer.ui.ReportPlugin;
import org.eclipse.birt.report.model.api.DesignElementHandle;
import org.eclipse.birt.report.model.api.ListGroupHandle;
import org.eclipse.birt.report.model.api.activity.SemanticException;
import org.eclipse.draw2d.IFigure;
import org.eclipse.gef.EditPart;
import org.eclipse.gef.EditPolicy;
import org.eclipse.gef.Request;
import org.eclipse.gef.RequestConstants;
/**
 * List element edit part.
 * 
 */
public class ListEditPart extends ReportElementEditPart