bugfix: use strict
bugfix: use strict

Former-commit-id: 21cec9855b19f68bbf600553e927deedafa0d510

daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf,daejunpark/jsaf