Bug 105697 [Undo] - OperationHistoryEvent - cannot distinguish between canceled event or failed event
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
private void notifyUndone(IUndoableOperation operation) {
		if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> UNDONE ");  
			System.out.print(operation);
			System.out.println();
		}
		notifyListeners(new OperationHistoryEvent(OperationHistoryEvent.UNDONE,
				this, operation));
	}
	/*
	 * Notify listeners that an operation has been undone.
	 */
	private void notifyChanged(IUndoableOperation operation) {
		if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> OPERATION_CHANGED ");  
			System.out.print(operation);
			System.out.println();
		}
		notifyListeners(new OperationHistoryEvent(
				OperationHistoryEvent.OPERATION_CHANGED, this, operation));
	}
	/*
	 * A history notification is about to be sent. Notify the operation before
	 * hand if it implements IHistoryNotificationAwareOperation.
	 * 
	 * This method is provided for legacy undo frameworks that rely on
	 * notification from their undo managers before any listeners are notified
	 * about changes in the operation.
	 */
	private void preNotifyOperation(IUndoableOperation operation,