Summary:
This PR split PointPropType.js into PointPropType.js with Flow definition and Libraries/DeprecatedPointPropType.js remaining with PropTypes definition.
Related to #21342
Pull Request resolved: https://github.com/facebook/react-native/pull/21355
Differential Revision: D10081399
Pulled By: TheSavior
fbshipit-source-id: 2283ff3fbda6b0f525742336f92fd6279250b874