Typing ViewProp, ImageProp
Typing ViewProp, ImageProp

Summary:
Tightening these types.

We can't type TextProp the same way yet because of something fishy in Flow:

https://flow.org/try/#0KYDwDg9gTgLgBDAnmYcAqoYGUkBtUC8cA3gD4BQccAZhAHYwBiAhgLYCWuiAXHAM4wo7OgHMANJRr1s7AF7BedAK6sARsCgTSAXwDc5cqEiwEyVIwAiWRtJyJ8cImUm0GLDl14ChorXoNG0PBIKOiYdvgAClAQYI5wACQASsDMACYA8nRcADwJWAAWzCg5GCDYeMAAfFW6cAD09XAprBAAbqjJqZnZiHDMdGkIBagaMVBwIhDAfP0A7syIBgDG9AJwllgRChtWNgzb8cQu0u6cPHAA5LQQlxL+5Kt062UV9sAAasxQvK-b0bF4pttrogA

Reviewed By: olegbl

Differential Revision: D7165134

fbshipit-source-id: 2fd3de2af8bdc53231d59de71def1e6a7221aff7

myntra/react-native,javache/react-native,janicduplessis/react-native,pandiaraj44/react-native,facebook/react-native,hammerandchisel/react-native,javache/react-native,exponent/react-native,exponent/react-native,arthuralee/react-native,javache/react-native,exponentjs/react-native,hammerandchisel/react-native,facebook/react-native,exponent/react-native,pandiaraj44/react-native,myntra/react-native,myntra/react-native,javache/react-native,hammerandchisel/react-native,hoangpham95/react-native,myntra/react-native,facebook/react-native,exponent/react-native,arthuralee/react-native,arthuralee/react-native,hoangpham95/react-native,javache/react-native,exponentjs/react-native,myntra/react-native,hoangpham95/react-native,hoangpham95/react-native,javache/react-native,facebook/react-native,pandiaraj44/react-native,exponentjs/react-native,hammerandchisel/react-native,pandiaraj44/react-native,myntra/react-native,pandiaraj44/react-native,exponent/react-native,janicduplessis/react-native,hammerandchisel/react-native,myntra/react-native,exponentjs/react-native,hammerandchisel/react-native,hoastoolshop/react-native,hoastoolshop/react-native,myntra/react-native,exponent/react-native,facebook/react-native,facebook/react-native,facebook/react-native,exponentjs/react-native,javache/react-native,exponentjs/react-native,janicduplessis/react-native,hoangpham95/react-native,arthuralee/react-native,hammerandchisel/react-native,janicduplessis/react-native,exponent/react-native,pandiaraj44/react-native,hoangpham95/react-native,hoastoolshop/react-native,pandiaraj44/react-native,javache/react-native,janicduplessis/react-native,hoastoolshop/react-native,hoastoolshop/react-native,hoastoolshop/react-native,hoastoolshop/react-native,facebook/react-native,hoastoolshop/react-native,pandiaraj44/react-native,hoangpham95/react-native,exponentjs/react-native,facebook/react-native,javache/react-native,exponent/react-native,exponentjs/react-native,janicduplessis/react-native,arthuralee/react-native,hoangpham95/react-native,hammerandchisel/react-native,janicduplessis/react-native,myntra/react-native,janicduplessis/react-native