PropTypes.oneOf relies upon stringification when using Symbols

[ZebraFlesh]

Do you want to request a feature or report a bug?
Bug

What is the current behavior?
React.PropTypes.oneOf prints a less than helpful error message when passed a Symbol which is not in the target value set: Failed prop type: Cannot convert a symbol to a string

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://jsfiddle.net or similar.

http://codepen.io/anon/pen/BWdEKb?editors=1011#0

What is the expected behavior?
oneOf prints the same or similar helpful error message that other primitive types get:
Failed prop type: Invalid prop `symbolSize` of value `Symbol(medium)` supplied to `Thing`, expected one of [Symbol(small),Symbol(large)].

Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?
React 15.4.2
macOS 10.12.3 / Safari 10.0.3 and Chrome 57.0.2987.98
Never worked

[aweary]

PropTypes have been removed from React core and now exist as a separate package prop-types. Any future feature requests, bug reports, or changes should be directed to the new repo at https://github.com/reactjs/prop-types.

[ljharb]

Fixed in facebook/prop-types#224.