Summary:
Now intrinsic content size of <Image> is implemented natively on iOS and now it is actually
`intrinsicContentSize`, not just overrided `height` and `width` styles (which was incorrect and hacky).
This change also removes support of nested content inside <Image>.
This is a first commit in the row where we improve <Image> implementation.
Reviewed By: mmmulani
Differential Revision: D5189017
fbshipit-source-id: eab3defa3d86a5d4219b4f4925ab7460b58d760f