React.lazy makes Route's proptypes fail

Hello,

The newly introduced React.lazy for easy code-splitting is making the Route component proptypes to fail with the warning :

Warning: Failed prop type: Invalid prop `component` of type `object` supplied to `Route`, expected `function`.

Version

react-router-dom: 4.4.0-beta.4 react: 16.6.0

Test Case

I took the official example from here : https://reactjs.org/docs/code-splitting.html#route-based-code-splitting

https://codesandbox.io/s/xp2nwl2qxw

[tylerwray]

@rnnyrk I just did the following for now 🤷‍♂️

const Home = React.lazy(() => import('./Home')

<Route exact path="/" component={props => <Home {...props} />} />

[wulucxy]

@pshrmn hey，when will you publish 4.4.0 version，this is a common problem。