function assignInDefaults(objValue, srcValue, key, object) {
  if (objValue === undefined ||
      (eq(objValue, objectProto$2[key]) && !hasOwnProperty$5.call(object, key))) {
    return srcValue;
  }
  return objValue;
}
Used by `_.defaults` to customize its `_.assignIn` use.

@private
@param {*} objValue The destination value.
@param {*} srcValue The source value.
@param {string} key The key of the property to assign.
@param {Object} object The parent object of `objValue`.
@returns {*} Returns the value to assign.