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
partDescriptor.setAllowMultiple(multipleAllowed);
		partDescriptor.setElementId("partId");
		application.getDescriptors().add(partDescriptor);
		stack.setSelectedElement(part);
		window.setSelectedElement(stack);
		application.setSelectedElement(window);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		MPart createdPart = partService.createPart("partId");
		MPart shownPart = partService.showPart(createdPart, partState);
		assertNotNull(shownPart);
		if (multipleAllowed) {
			assertEquals(createdPart, shownPart);
		} else {
			assertEquals(part, shownPart);
		}
	}
	public void testShowPart_Part_MultipleExists_TrueACTIVATE() {
		testShowPart_Part_MultipleExists(true, PartState.ACTIVATE);
	}
	public void testShowPart_Part_MultipleExists_FalseACTIVATE() {
		testShowPart_Part_MultipleExists(false, PartState.ACTIVATE);
	}
	public void testShowPart_Part_MultipleExists_TrueVISIBLE() {
		testShowPart_Part_MultipleExists(true, PartState.VISIBLE);
	}
	public void testShowPart_Part_MultipleExists_FalseVISIBLE() {
		testShowPart_Part_MultipleExists(false, PartState.VISIBLE);
	}