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 (DEBUG_OPERATION_HISTORY_UNEXPECTED) {
			if (openComposite == null) {
				System.out
						.print("OPERATIONHISTORY >>> Attempted to close operation when none was open ");  
				System.out.println();
				return;
			}
		}
		if (openComposite != null) {
			if (DEBUG_OPERATION_HISTORY_OPENOPERATION) {
				System.out.print("OPERATIONHISTORY >>> Closing operation ");  
				System.out.print(openComposite);
				System.out.println();
			}
			
			
			
			
			if (operationOK) {
				if (mode == EXECUTE)
					notifyDone(openComposite);
				if (addToHistory)
					add(openComposite);
			} else {
				if (mode == EXECUTE)
					notifyNotOK(openComposite);
			}
			openComposite = null;
		}
	}