Fix typo in super call of validate

issue3417
review1131002
(transplanted from 545ea40180c9a8c89e845d70eb90de92498ba214)

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extra : transplant_source : T%5E%A4%01%80%C9%A8%C8%9E%84%5Dp%EB%90%DE%92I%8B%A2%14