A question about the EnforcedProperty of optimizer

[feiniaofeiafei]

Bug Report

Summary

In the file optimizer_task.cpp, the function "void OptimizeExpressionCostWithEnforcedProperty::Execute()".
In the 341 line, "cur_group->SetExpressionCost(memo_enforced_expr, cur_total_cost_, output_prop->Copy())",
why the third arguement is "output_prop->Copy()" instead of extended_prop_set, I think the memo_enforced_expr can
satisfied the extended_prop_set.