Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/42402
Now that we have 2 top level directories for JS files in the `react-native` package, we need to choose where to put the native module and native component specs, because our current infra only supports a single directory.
The options we had are:
1. Keep specs in the current directory (`Libraries`). This is a problem because it encourages us to keep adding modules in this "deprecated" directory.
2. Move specs to the new `src` directory. This requires moving the current files, but from now only we can create new specs in a private directory.
3. Modify the infra to allow multiple directories. This changes the public API for something it's likely only going to be used here.
In this PR I went for option 2) because it's the most future-proof, even though it requires a little bit more work now. I created a script to automatically copy all the specs for modules and components to `src/private/specs/components` and `src/private/specs/modules`, and changed their current locations to serve as a proxy for the new location (to avoid breaking a potentially public API).
`src/private/specs` isn't meant to be their final location. We should probably still colocate native module/component specs with the rest of their code, but we can do so when we move the code from `Libraries` to `src/private`.
Changelog: [internal]
Reviewed By: cortinico
Differential Revision: D52919566
fbshipit-source-id: 6de8a2d2b6077e4f884386567721c6bd2b88a5d3