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
String id = getOriginalId(eObject);
		if (id == null) {
			if (featureName == null || isDirectReference(featureName)) {
				
				
				return createNewReferenceElement(document, eObject);
			}
			return createUniqueReferenceElement(document, eObject);
		}
		Element referenceElement = document.createElement(REFERENCE_ELEMENT_NAME);
		referenceElement.setAttribute(APPLICATIONELEMENT_ELEMENTID_ATTNAME, id);
		return referenceElement;
	}
	private void appendReferenceElements(Document document, Element element, List<?> references) {
		for (Object reference : references) {
			Element ef = createReferenceElement(document, (EObject) reference, null);
			element.appendChild(ef);
		}
	}
	private Element createNewReferenceElement(Document document, EObject eObject) {
		Element referenceElement = createUniqueReferenceElement(document, eObject);
		
		
		referenceElement.setAttribute(UNSET_ATTNAME, UNSET_ATTVALUE_TRUE);
		
		referenceElement.setAttribute(TYPE_ATTNAME, eObject.getClass().getInterfaces()[0]
				.getCanonicalName());
		for (EStructuralFeature collectedFeature : collectFeatures(eObject)) {
			String featureName = collectedFeature.getName();