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 (part != null)
					activate(part);
			}
		});
		((EObject) me).eAdapters().add(0, new AdapterImpl() {
			@Override
			public void notifyChanged(Notification msg) {
				if (ApplicationPackage.Literals.MPART__ACTIVE_CHILD.equals(msg
						.getFeature())) {
					MStack sm = (MStack) msg.getNotifier();
					MPart<?> selPart = sm.getActiveChild();
					CTabFolder ctf = (CTabFolder) ((MStack) msg.getNotifier())
							.getWidget();
					CTabItem item = findItemForPart(sm, selPart);
					if (item != null) {
						if (ctf.getSelection() != item)
							ctf.setSelection(item);
					}
				}
			}
		});
	}
	private void showTab(MItemPart<?> part) {
		CTabFolder ctf = (CTabFolder) getParentWidget(part);
		Control ctrl = (Control) part.getWidget();
		CTabItem cti = findItemForPart(part.getParent(), part);
		cti.setControl(ctrl);
		ToolBar tb = getToolbar(part);
		if (tb != null) {
			Control curTR = ctf.getTopRight();