code: function sameValueZero(value1, value2) {
    // Normal values and check for 0 / -0
    if (value1 === value2) {
      return value1 !== 0 || 1 / value1 === 1 / value2;
    }
    // NaN
    return value1 !== value1 && value2 !== value2;
  }
docs: Object.is/sameValueZero polyfill.
  
  @api private
  @param {*} value1
  @param {*} value2
  @return {boolean}
   TODO: Move to library