Thanks for submitting a pull request! Please provide enough information so that others can review your pull request:

(You can skip this if you're fixing a typo or adding an app to the Showcase.)

Explain the **motivation** for making this change. What existing problem does the pull request solve?

Example: When "Adding a function to do X", explain why it is necessary to have a way to do X.

**Test plan (required)**

Demonstrate the code is solid. Example: The exact commands you ran and their output, screenshots / videos if the pull request changes UI.

Make sure tests pass on both Travis and Circle CI.

**Code formatting**

See the simple [style guide](https://github.com/facebook/react-native/blob/master/CONTRIBUTING.md#style-guide).
