Summary:
Platforms that plug in to react-native may require additional props that are specific to those platforms. For example, already in react-native there are props that are specific to Android (`accessibilityComponentType`, `needsOffscreenAlphaCompositing`, etc.), props that are specific to iOS (`accessibilityTraits`, `shouldRasterizeIOS`, etc.) and props that are specific to tvOS (`isTVSelectable`, `tvParallaxProperties`, etc.).
I need to add properties to `react-native-windows`, and I'd prefer not to override the entire `ViewPropTypes` file as it is a risk that things in react-native-windows fall out of sync with react-native.
Fixes#15173
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Closes https://github.com/facebook/react-native/pull/15175
Differential Revision: D5481444
Pulled By: hramos
fbshipit-source-id: 3da08716d03ccdf317ec447536eea3699dd7a760
59105f6b1e