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
ModelDelta delta = createUnorderedChainedAttributeDelta(object,
									attributeFeature, item, attributeName);
							deltas.add(delta);
						} else if (isStringToStringMap(attributeName)) {
							EStructuralFeature feature = getStructuralFeature(object, attributeName);
							EMap map = (EMap) object.eGet(feature);
							NodeList attributes = (NodeList) item;
							for (int j = 0; j < attributes.getLength(); j++) {
								Node entry = attributes.item(j);
								if (entry instanceof Element) {
									Element keyValue = (Element) entry;
									map.put(keyValue.getAttribute(ENTRY_ATTVALUE_KEY), keyValue
											.getAttribute(ENTRY_ATTVALUE_VALUE));
								}
							}
						} else {
							object.eSet(attributeFeature, getValue(attributeFeature, item
									.getAttribute(attributeName)));
						}
					}
				}
			}
		}
		return compositeDelta;
	}
	private ModelDelta createUnorderedChainedAttributeDelta(EObject object,
			EStructuralFeature feature, Element node, String featureName) {
		Set<Object> values = new HashSet<Object>();
		NodeList attributes = (NodeList) node;
		for (int j = 0; j < attributes.getLength(); j++) {