Summary:
- [x] Explain the **motivation** for making this change.
- [ ] ~Provide a **test plan** demonstrating that the code is solid.~
- [x] Match the **code formatting** of the rest of the codebase.
- [x] Target the `master` branch, NOT a "stable" branch.
The key name required to access the CameraRoll in iOS is incorrect.
Closes https://github.com/facebook/react-native/pull/13755
Differential Revision: D4994048
Pulled By: javache
fbshipit-source-id: 9ec2f793f03f529e9cf0f89106f88445fde50f2a