Bug 94400 [Undo] - After successful undo, should operation be disposed by framework if it cannot be redone?
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
/*
		 * If we are in the middle of an open batch, then we will add this
		 * operation's contexts to the open operation rather than add the
		 * operation to the history. We will still execute it, but will dispose
		 * of it afterward. Operations triggered during an operation are assumed
		 * to be model-related and we assume the undo of this related operation
		 * will be triggered automatically by the undo of the batching
		 * operation.
		 */
		boolean merging = false;
		if (openComposite != null) {
			
			
			if (openComposite == operation) {
				return IOperationHistory.OPERATION_INVALID_STATUS;
			}
			openComposite.add(operation);
			merging = true;
		}
		/*
		 * Execute the operation
		 */
		if (!merging)
			notifyAboutToExecute(operation);
		IStatus status;
		try {
			status = operation.execute(monitor, info);
		} catch (OperationCanceledException e) {
			status = Status.CANCEL_STATUS;
		} catch (ExecutionException e) {