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
while (container != rootObject) {
				container = getOriginalContainer(container);
				if (container == null) {
					return null;
				}
			}
		}
		return getResourceId(reference, originalContainer);
	}
	/**
	 * Creates an XML element that will capture the delta that occurred in the object.
	 * 
	 * @param document
	 *            the root XML document
	 * @param object
	 *            the object that has changed
	 * @param featureChange
	 *            the captured information about the change
	 * @param featureName
	 *            the name of the feature that has changed
	 * @return the XML element about the change
	 */
	private Element createDeltaElement(Document document, EObject object,
			FeatureChange featureChange, String featureName) {
		EStructuralFeature feature = featureChange.getFeature();
		if (object.eIsSet(feature)) {
			return createSetDeltaElement(document, object, featureChange, featureName, feature);
		}
		return createUnsetDeltaElement(document, featureChange, featureName);
	}