Bug 317954 Version deltas file so that incompatible changes will be ignored
The deltas file needs to be versioned so that incompatible changes will be discarded allowing the workbench to be constructed as if there were no deltas in existence.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/XMLModelReconciler.java
List<Object> references) {
		String typeName = element.getAttribute(TYPE_ATTNAME);
		String namespace = element.getAttribute(NAMESPACE_ATTNAME);
		EObject object = createObject(namespace, typeName);
		CompositeDelta compositeDelta = new CompositeDelta(object);
		E4XMIResource resource = (E4XMIResource) rootObject.eResource();
		resource.setInternalId(object, element.getAttribute(XMIID_ATTNAME));
		NodeList elementAttributes = (NodeList) element;
		for (int i = 0; i < elementAttributes.getLength(); i++) {
			Node node = elementAttributes.item(i);
			if (node instanceof Element) {
				Element item = (Element) node;
				if (!isUnset(item)) {
					String attributeName = item.getNodeName();
					EStructuralFeature attributeFeature = getStructuralFeature(object,
							attributeName);
					if (attributeFeature != null) {
						if (isDirectReference(attributeName)) {
							String id = item.getAttribute(attributeName);
							Object objectReference = findReference(references, id);
							if (objectReference == null) {
								objectReference = createObject(deltas,
										getFirstElement((NodeList) item), references);
							}
							IDelta delta = new EMFModelDeltaSet(object, attributeFeature,
									objectReference);
							compositeDelta.add(delta);
						} else if (isIndirectReference(attributeName)) {
							String id = item.getAttribute(attributeName);
							Object objectReference = findReference(references, id);