Bug 334559 EPartService's part searching path may not include parts outside of the active perspective
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPart part = BasicFactoryImpl.eINSTANCE.createPart();
		part.setVisible(visible);
		window.getChildren().add(part);
		if (selected) {
			window.setSelectedElement(part);
		}
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		assertEquals(visible, partService.isPartVisible(part));
		partService = (EPartService) part.getContext().get(
				EPartService.class.getName());
		assertEquals(visible, partService.isPartVisible(part));
	}
	public void testIsPartVisible_NotInStackTrueTrue() {
		testIsPartVisible_NotInStack(true, true);
	}
	public void testIsPartVisible_NotInStackFalseTrue() {
		testIsPartVisible_NotInStack(false, true);
	}
	public void testIsPartVisible_NotInStackFalseFalse() {
		testIsPartVisible_NotInStack(false, false);
	}
	public void testIsPartVisible_ViewVisible() {
		MApplication application = createApplication("partId");