message: utils/is: fix plainObject on constructorless thing
diff: @@ -25,7 +25,9 @@ export const element = thing => {
  : thing.nodeType === 1 && typeof thing.nodeName === 'string');
  };
  -export const plainObject = thing => object(thing) && thing.constructor.name === 'Object';
  +export const plainObject = thing => object(thing) &&
  + !!thing.constructor &&
  + thing.constructor.name === 'Object';
  export const array = thing => (object(thing)
  && (typeof thing.length !== 'undefined')
  