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
notifyAboutToExecute(operation);
		IStatus status;
		try {
			status = operation.execute(monitor, info);
		} catch (OperationCanceledException e) {
			status = Status.CANCEL_STATUS;
		} catch (ExecutionException e) {
			notifyNotOK(operation);
			throw e;
		} catch (Exception e) {
			notifyNotOK(operation);
			throw new ExecutionException(
					"While executing the operation, an exception occurred", e); 
		}
		
		
		if (!merging) {
			if (status.isOK()) {
				notifyDone(operation);
				
				 
				 
				
				
				
				if (operation.canUndo()) {
					add(operation);
				} else {