parseObjectAssignmentPattern_() {
    return this.parseObjectPattern_(false);
  }
ObjectAssignmentPattern[Yield] :
  { }
  { AssignmentPropertyList[?Yield] }
  { AssignmentPropertyList[?Yield] , }

AssignmentPropertyList[Yield] :
  AssignmentProperty[?Yield]
  AssignmentPropertyList[?Yield] , AssignmentProperty[?Yield]

AssignmentProperty[Yield] :
  IdentifierReference[?Yield] Initializer[In,?Yield]opt
  PropertyName : AssignmentElement[?Yield]