Hooks API - Context

[bryphe]

Was just working on porting Oni2 over to the latest Revery + Brisk reconciler, and reminded me of the context issue. We're using context right now to provide a context-based ThemeProvider.

A potential API could look like:

• createContext: 'a -> context('a)
• Hooks.useContext: context('a) -> 'a
• getProvider: context('a) -> providerComponent('a)

I believe handling the typing correctly in terms of passing the nested context down will be challenging - so we might need to alter the API to make it workable in a strongly-typed environment w/o resorting to Obj.magic.

Not a blocker, I'll workaround it, but just wanted to log an issue to start the discussion.