Remove react prop-types for production build (fix)

[spartDev]

Since react-media 1.9.0 and adding the __DEV__ boolean global, there is a problem in the final production build.
When importing the lib in your project an error occurred :

ReferenceError: __DEV__ is not defined

I use babel-plugin-transform-react-remove-prop-types to remove react prop-typesin production instead of using the __DEV__ global.

[edorivai]

Thanks for the quick PR. I'm verifying some stuff on my end, and plan to roll this patch out today!

[mjackson]

The thing that was nice about using the __DEV__ flag is that we can still include prop-types in development but remove them in production. Also, __DEV__ works for more than just prop-types; we can use it anywhere we want to put development-only code.

The way this PR is implemented, people using our ESM build will never get prop-types warnings, even in development where they could be useful.

It looks like it wasn't working because I forgot to include babel-plugin-dev-expression in our babel config. I'll go ahead and revert this commit and fix it another way.

Thanks for the catch, @spartDev :)

[spartDev]

@mjackson I understand about using __DEV__ flag but babel-plugin-transform-react-remove-prop-types remove import reference too.
What about create an esmconfig for production?

[mjackson]

The import reference will be removed by webpack in production mode if it isn't used anywhere in our code. We don't need an esm build for production because ESM imports are unconditional, so everyone imports the same build and then uses process.env.NODE_ENV (same as in React) to create their own production build.

[spartDev]

@mjackson fair point!