function makeSelectionUndoDatum(id, obj, isSelection) {
  return isSelection
    ? {
        id,
        width: obj.width,
        height: obj.height,
        top: obj.top,
        left: obj.left,
        angle: obj.angle,
        scaleX: obj.scaleX,
        scaleY: obj.scaleY,
      }
    : extend({ id }, obj);
}
Make undo datum
@param {number} id - object id
@param {fabric.Object} obj - selection object
@param {boolean} isSelection - whether or not object is selection
@returns {Object} undo datum
@private