Bug 283340 NPE is thrown when last child of stack is removed
1. Close the 'Outline' view. 2. That stack is now gone. An NPE is logged. java.lang.NullPointerException at org.eclipse.e4.workbench.ui.renderers.swt.StackModelFactory.childRemoved(StackModelFactory.java:315) at org.eclipse.e4.workbench.ui.renderers.swt.StackModelFactory$2.notifyChanged(StackModelFactory.java:265) at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:280) at org.eclipse.e4.ui.model.internal.application.MPartImpl.setVisible(MPartImpl.java:457) at org.eclipse.e4.workbench.ui.renderers.swt.StackModelFactory$5.close(StackModelFactory.java:344) at org.eclipse.swt.custom.CTabFolder.onMouse(CTabFolder.java:2199) at org.eclipse.swt.custom.CTabFolder$1.handleEvent(CTabFolder.java:327)
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
if (curTR != null)
				curTR.dispose();
			if (tb.getSize().y > ctf.getTabHeight())
				ctf.setTabHeight(tb.getSize().y);
			
			
			String cssClassName = (String) ctf
					.getData("org.eclipse.e4.ui.css.CssClassName"); 
			stylingEngine.setClassname(tb, cssClassName);
			ctf.setTopRight(tb, SWT.RIGHT);
			ctf.layout(true);
			
			
			
			
			
			
			
			
			
			ctf.notifyListeners(SWT.Resize, null);
		}
	}
	private ToolBar getToolbar(MItemPart<?> part) {
		if (part.getToolBar() == null && part.getMenu() == null)
			return null;
		CTabFolder ctf = (CTabFolder) getParentWidget(part);
		ToolBar tb;
		MToolBar tbModel = part.getToolBar();
		if (tbModel != null) {