React.createClass is deprecated

[stevenhao]

This issue causes a development-only warning in projects using the mdg:flow-router-extensions package.
Warning: ReactClassPrototypePrototype: React.createClass is deprecated and will be removed in version 16. Use plain JavaScript classes instead. If you're not yet ready to migrate, create-react-class is available on npm as a drop-in replacement.

This issue is a bit tricky, because we already correctly extend the React.Component class instead of using React.createClass when making components. The only time React.createClass is called is here. It appears that this code snippet follows the discussion in this thread. This hack is necessary is to account for the subtle differences between classes created by React.createClass and the React.Component class.

There are a number of solutions that should work, including:

• Use the create-react-class package (which can be used as a drop-in replacement)
• Use the undocumented prototype property React.Component.prototype.isReactComponent