Bug 303305 EPS cannot handle being asked for from the application's context
Right now we have this... @Inject @Named(EPartService.PART_SERVICE_ROOT) private MElementContainer<MUIElement> rootContainer; ...which will be 'null' if the question was posed to the application's context. Right now, I cannot use EPS in the SaveHandler because I get an (effectively) useless EPartService (filled with null fields).
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/PartServiceImpl.java
void setPart(@Optional @Named(IServiceConstants.ACTIVE_PART) MPart p) {
		activePart = p;
		if (constructed && p != null) {
			firePartActivated(p);
		}
	}
	@PostConstruct
	void postConstruct() {
		eventBroker.subscribe(UIEvents.buildTopic(UIEvents.ElementContainer.TOPIC,
				UIEvents.ElementContainer.SELECTEDELEMENT), selectedHandler);
		constructed = true;
	}
	@PreDestroy
	void preDestroy() {
		constructed = false;
		eventBroker.unsubscribe(selectedHandler);
	}
	private void firePartActivated(MPart part) {
		for (Object listener : listeners.getListeners()) {
			((IPartListener) listener).partActivated(part);
		}
	}
	private void firePartBroughtToTop(MPart part) {
		for (Object listener : listeners.getListeners()) {
			((IPartListener) listener).partBroughtToTop(part);
		}
	}
	public void addPartListener(IPartListener listener) {
		listeners.add(listener);
	}