Summary:
Thanks for submitting a pull request! Please provide enough information so that others can review your pull request:
> **Unless you are a React Native release maintainer and cherry-picking an *existing* commit into a current release, ensure your pull request is targeting the `master` React Native branch.**
Explain the **motivation** for making this change. What existing problem does the pull request solve?
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Demonstrate the code is solid. Example: The exact commands you ran and their output, screenshots / videos if the pull request changes UI.
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Closes https://github.com/facebook/react-native/pull/10413
Differential Revision: D4028108
fbshipit-source-id: 99a864dfda578d640f582b296583591415ba26cd
Summary: Move all JS to a js/ subfolder so we get some overview of this folder again.
Reviewed By: bestander
Differential Revision: D3542598
fbshipit-source-id: 7637133fe4152f4d39e461b443b38510272d5bc8
