Bug 324841 Launching with -persistState false leads to an NPE
Like reported on the newsgroup launching with this flag set to true leads to an NPE because we still try to load the deltas.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/ResourceHandler.java
@Inject
	private Logger logger;
	@Inject
	private IEclipseContext context;
	@Inject
	@Named(E4Workbench.INITIAL_WORKBENCH_MODEL_URI)
	private URI applicationDefinitionInstance;
	@Inject
	@Named(E4Workbench.INSTANCE_LOCATION)
	private Location instanceLocation;
	private boolean saveAndRestore;
	private boolean clearPersistedState;
	/**
	 * Dictates whether the model should be stored using EMF or with the merging algorithm.
	 * https://bugs.eclipse.org/bugs/show_bug.cgi?id=295524
	 */
	private boolean deltaRestore = true;
	@Inject
	public ResourceHandler(@Named(E4Workbench.PERSIST_STATE) boolean saveAndRestore,
			@Named(E4Workbench.CLEAR_PERSISTED_STATE) boolean clearPersistedState,
			@Named(E4Workbench.DELTA_RESTORE) boolean deltaRestore) {
		this.saveAndRestore = saveAndRestore;
		this.clearPersistedState = clearPersistedState;
		this.deltaRestore = deltaRestore;
	}
	@PostConstruct
	void init() {
		resourceSetImpl = new ResourceSetImpl();
		resourceSetImpl.getResourceFactoryRegistry().getExtensionToFactoryMap()
				.put(Resource.Factory.Registry.DEFAULT_EXTENSION, new E4XMIResourceFactory());