Summary:
By depending on react-native, these files can't be flow strict until index.js is flow strict. By depending on the internals directly they can be flow strict as soon as their dependents are flow strict.
Changelog:
[Internal] Refactoring some core file imports to depend on internals directly
Reviewed By: zackargyle
Differential Revision: D18828324
fbshipit-source-id: 2a347c4e234a64edbb3e6f0ef6387ef1ce78badc