RFC: Remove return types from React components

[eagerestwolf]

Describe the feature in detail (code, mocks, or screenshots encouraged)

As discussed in #2733, the next item I would like to tackle is refactoring the components to remove the return types.

This change has no performance change at all, but that doesn't mean there shouldn't be a change. There are currently 7 possible return types for a React component:

From React:

• React.FC: This is what Skeleton currently uses. This defines a functional component
• React.ReactElement: This is what JSX.Element gets mapped to. It's basically what it says on the tin, an element in a React DOM
• React.ReactPortal: This is a ReactElement with a children property
• React.ReactNode: This basically describes any node that can be inserted into a React DOM. This is what JSX.IntrinsicElement gets mapped to by default, unless overridden
• React.JSX.Element: This is the replacement for the depreciated JSX global namespace

From TypeScript:

• JSX.Element: This maps to React.ReactElement in a React project, but the JSX global namespace is depreciated
• JSX.IntrinsicElement: This maps to React.ReactNode in a React project, but again the JSX global namespace is depreciated

As you can see, there are a lot of possible return types in React. The general consensus used to be to use React.FC, but React.FC has it's own fair share of problems. Then the consensus became to use JSX.Element, but that also had issues since it's kind of a black box as it's a generic ReactElement with no type parameters passed to it. So, now we're left in a strange spot, you can either type everything yourself manually (i.e. attempting to predict the outputted types from React.createElement) or just letting TypeScript infer the type. The general consensus amongst the React community has been to just allow TypeScript to infer the type.

I know this is a lot to take in. Please feel free to look over the links provided below. No change will be made to the code until there has been at least a week or so to allow for comment. The main person who should probably be involved in this one for now is @Hugos68 since he has done most of the React work to this point, and Chris is taking some much needed time off; however, if there is any feedback from the community that is appreciated as well.

What type of pull request would this be?

Other

Provide relevant links or additional information.

https://github.com/DefinitelyTyped/DefinitelyTyped/blob/266eae5148c535e6b41fe5d0adb2ad23f302bc8a/types/react/index.d.ts#L3182

facebook/create-react-app#8177

typescript-cheatsheets/react#643

https://stackoverflow.com/questions/76224848/what-is-the-correct-return-type-replacement-for-jsx-element-after-the-global-jsx

https://stackoverflow.com/questions/58123398/when-to-use-jsx-element-vs-reactnode-vs-reactelement