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
MArea area = AdvancedFactoryImpl.eINSTANCE.createArea();
		window.getSharedElements().add(area);
		MPart part = BasicFactoryImpl.eINSTANCE.createPart();
		window.getSharedElements().add(part);
		MPerspectiveStack perspectiveStack = AdvancedFactoryImpl.eINSTANCE
				.createPerspectiveStack();
		window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspective = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspective);
		perspectiveStack.setSelectedElement(perspective);
		MPlaceholder areaPlaceholder = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		areaPlaceholder.setRef(area);
		part.setCurSharedRef(areaPlaceholder);
		perspective.getChildren().add(areaPlaceholder);
		perspective.setSelectedElement(areaPlaceholder);
		MPlaceholder partPlaceholder = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		partPlaceholder.setRef(part);
		part.setCurSharedRef(partPlaceholder);
		area.getChildren().add(partPlaceholder);
		area.setSelectedElement(partPlaceholder);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = window.getContext().get(EPartService.class);
		partService.hidePart(part, force);
		assertFalse(partPlaceholder.isToBeRendered());
	}