Bug 329310 Part service does not autogenerate stacks if the last container is not one
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		partStack.getChildren().add(partA);
		partStack.setSelectedElement(partA);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		partStack.getChildren().add(partB);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		
		partStack.getChildren().remove(partA);
		
		partService.showPart(partB, partState);
		assertEquals(partB, partStack.getSelectedElement());
	}
	public void testShowPart_Bug328078_CREATE() {
		testShowPart_Bug328078(PartState.CREATE);
	}
	public void testShowPart_Bug328078_VISIBLE() {
		testShowPart_Bug328078(PartState.VISIBLE);
	}
	public void testShowPart_Bug328078_ACTIVATE() {
		testShowPart_Bug328078(PartState.ACTIVATE);
	}
	private void testHidePart_Bug325148(boolean force) {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);