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
MPerspectiveStack perspectiveStack = AdvancedFactoryImpl.eINSTANCE
				.createPerspectiveStack();
		window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspective = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspective);
		perspectiveStack.setSelectedElement(perspective);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EModelService modelService = window.getContext().get(
				EModelService.class);
		EPartService partService = window.getContext().get(EPartService.class);
		MPlaceholder placeholder = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		placeholder.setRef(part);
		part.setCurSharedRef(placeholder);
		partService.showPart(part, PartState.ACTIVATE);
		List<MPart> parts = modelService.findElements(perspective,
				part.getElementId(), MPart.class, null);
		assertEquals(1, parts.size());
		assertEquals(part, parts.get(0));
		List<MPlaceholder> placeholders = modelService.findElements(
				perspective, part.getElementId(), MPlaceholder.class, null);
		assertEquals(1, placeholders.size());
		assertEquals(placeholder, placeholders.get(0));
		assertEquals(part.getCurSharedRef(), placeholders.get(0));
		assertEquals(part, placeholders.get(0).getRef());
	}
	public void testShowPart_Bug329310_01() {