Summary:
This is first PR from the series I am going to be sending as a result of fixing 0.50-stable test suite. This one removes `mockFS` dependency that has been causing failures on Node 6.x container.
Here's build before this change: https://circleci.com/gh/facebook/react-native/22529
Here's build after this change: https://circleci.com/gh/facebook/react-native/22538 (green)
Note that the CI may be still red as there are other PRs to be addressed. You can see this in the wild on 0.50.
Closes https://github.com/facebook/react-native/pull/16301
Differential Revision: D6031352
Pulled By: hramos
fbshipit-source-id: 5c97ae6c87864c094e29e5d8987521071c67f5bd
1f498010e8