Bug 120519 NullPointerException is thrown out when deleting a list group.
Description: NullPointerException is thrown out when deleting a list group. Steps to reproduce: 1. Save attached design file as a new file. 2. Right click on list group header and select "delete group". NullPointerException is thrown out. ava.lang.NullPointerException at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportElementEditPart.getRefreshManager(ReportElementEditPart.java:713) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportElementEditPart.refreshVisuals(ReportElementEditPart.java:513) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportDesignEditPart.notifyChildrenDirty(ReportDesignEditPart.java:219) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportElementEditPart.notifyChildrenDirty(ReportElementEditPart.java:688) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ListEditPart.notifyChildrenDirty(ListEditPart.java:297) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportElementEditPart.markDirty(ReportElementEditPart.java:669) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ReportElementEditPart.markDirty(ReportElementEditPart.java:655) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ListEditPart.elementChanged(ListEditPart.java:103) at org.eclipse.birt.report.model.core.DesignElement.broadcast(DesignElement.java:776) at org.eclipse.birt.report.model.activity.NotificationRecordTask.doTask(NotificationRecordTask.java:199) at org.eclipse.birt.report.model.activity.FilterEventsCompoundRecord.performPostTasks(FilterEventsCompoundRecord.java:76) at org.eclipse.birt.report.model.activity.ActivityStack.commit(ActivityStack.java:704) at org.eclipse.birt.report.model.command.ContentCommand.doRemove(ContentCommand.java:465) at org.eclipse.birt.report.model.command.ContentCommand.remove(ContentCommand.java:351) at org.eclipse.birt.report.model.api.DesignElementHandle.drop(DesignElementHandle.java:1183) at org.eclipse.birt.report.designer.core.model.schematic.ListHandleAdapter.removeGroup(ListHandleAdapter.java:213) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.editparts.ListEditPart.removeGroup(ListEditPart.java:282) at org.eclipse.birt.report.designer.internal.ui.editors.schematic.actions.DeleteListGroupAction.run(DeleteListGroupAction.java:59) at org.eclipse.jface.action.Action.runWithEvent(Action.java:996) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:538) at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:488) at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:400) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:843) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3080) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2713) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1699) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1663) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:367) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:143) at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:103) at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:226) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:376) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:163) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.eclipse.core.launcher.Main.invokeFramework(Main.java:334) at org.eclipse.core.launcher.Main.basicRun(Main.java:278) at org.eclipse.core.launcher.Main.run(Main.java:973) at org.eclipse.core.launcher.Main.main(Main.java:948)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentRecord.java
return container;
	}
	/**
	 * Not used in this class.
	 * 
	 * @return null is always returned.
	 * @see org.eclipse.birt.report.model.activity.AbstractElementRecord#getEvent()
	 */
	public NotificationEvent getEvent( )
	{
		return null;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.design.core.activity.SimpleRecord#perform(boolean)
	 */
	protected void perform( boolean undo )
	{
		ContainerSlot slot = container.getSlot( slotID );
		if ( add && !undo || !add && undo )
		{
			slot.insert( content, oldPosn );
			
			content.setContainer( container, slotID );
			
			
			if ( content.getRoot( ) != null )
				module.manageId( content, true, true );
		}