Bug 153038 NPE when delete master page content in old report design.
UI/org.eclipse.birt.report.designer.ui.editors.schematic/src/org/eclipse/birt/report/designer/internal/ui/editors/layout/ReportMasterPageEditor.java
/*************************************************************************************
 * Copyright (c) 2004 Actuate Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     Actuate Corporation - Initial implementation.
 ************************************************************************************/
package org.eclipse.birt.report.designer.internal.ui.editors.layout;
import org.eclipse.birt.report.designer.core.util.mediator.request.ReportRequest;
import org.eclipse.birt.report.designer.internal.ui.palette.MasterPagePaletteFactory;
import org.eclipse.birt.report.designer.internal.ui.util.ExceptionHandler;
import org.eclipse.birt.report.designer.ui.newelement.DesignElementFactory;
import org.eclipse.birt.report.model.api.MasterPageHandle;
import org.eclipse.birt.report.model.api.ModuleHandle;
import org.eclipse.birt.report.model.api.SimpleMasterPageHandle;
import org.eclipse.birt.report.model.api.command.ContentException;
import org.eclipse.birt.report.model.api.command.NameException;
import org.eclipse.gef.palette.PaletteRoot;
import org.eclipse.ui.IEditorPart;
/**
 * <p>
 * Report master page graphical editor.
 * </p>
 */
public class ReportMasterPageEditor extends