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
if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> OPERATION_ADDED ");  
			System.out.print(operation);
			System.out.println();
		}
		notifyListeners(new OperationHistoryEvent(
				OperationHistoryEvent.OPERATION_ADDED, this, operation));
	}
	/*
	 * Notify listeners that an operation is done executing.
	 */
	private void notifyDone(IUndoableOperation operation) {
		if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> DONE ");  
			System.out.print(operation);
			System.out.println();
		}
		notifyListeners(new OperationHistoryEvent(OperationHistoryEvent.DONE,
				this, operation));
	}
	/*
	 * Notify listeners that an operation did not succeed after an attempt to
	 * execute, undo, or redo was made.
	 */
	private void notifyNotOK(IUndoableOperation operation) {
		if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> OPERATION_NOT_OK ");  
			System.out.print(operation);
			System.out.println();
		}