check for same product in constraint for internal oderpoints

issue3591
review2721002
(transplanted from 203cecdea47d9daf7e53bf7d7070a3aa60806004)

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extra : transplant_source : %20%3C%EC%DE%A4%7D%9D%AF%7ES%BF%7Dpp%A3%AA%60%80%60%04