Summary:
This hasn't been used by React core for a while. It's unclear why it was in the first place.
We can move it back next to the Panresponder.
https://github.com/facebook/react/pull/12557
Reviewed By: sophiebits
Differential Revision: D7529949
fbshipit-source-id: ef9892cfa8d2d6768da216b81befabe02795a245
Sebastian Markbage