Summary:
Updates the return type of `createAnimatedComponent` to reflect the new behavior (where we forward the ref to the internal component).
I also improved the type annotation for `Props` so that we can still enforce that only valid prop names are supplied. (We still do not check the prop values because we do not currently have a good strategy for typing the "animated versions" of those.)
Changelog:
[General] [Changed] - Flow types for Animated components now validates prop names and yields the new component instance.
Reviewed By: TheSavior
Differential Revision: D18290473
fbshipit-source-id: 8c629ab6aff009ebe6dabca1683c99a357869977