Added failing test check for Route and forwardRef

[frehner]

Currently, Route uses the prop-type of func to check the Component prop.

However, that doesn't cover all valid React components, since React.forwardRef returns an object as noted here.

So this failing test is being added to help correct this at some point in the future.

I thought it may be nice to talk about possible solutions here as well:

• Wait until the proptypes package adds support for a Component type
• Change to a custom proptype function that can use react-is' isValidElementType to add the prop type check manually

Hopefully this is helpful!

[frehner]

Just checking in to see if this is helpful or if I should just close it out. :)

[mjackson]

Hi @frehner, thanks for the PR. Yes, I'm interested in fixing this. Maybe the best option for now is to just add a PropTypes.object to the array, and then upgrade to use a PropTypes.Component when that's released?

[mjackson]

Ah, just noticed this is a duplicate of #6327. Let's follow up there.