Summary:
Since alignItem works on the secondary axis, in the example, the value heigth: 50 should be deleted so that alignItem: 'stretch' can work. Not width: 50. In fact, width needs to be there, or else no component will be shown at all.
<!--
Thank you for sending the PR! We appreciate you spending the time to work on these changes.
Help us understand your motivation by explaining why you decided to make this change.
You can learn more about contributing to React Native here: http://facebook.github.io/react-native/docs/contributing.html
Happy contributing!
-->
(Write your motivation here.)
I'm going through the docs, that's why I found this. It's already tested!
Apologize if I'm contributing the wrong way. I read the instructions, but this is my first time ever, and will try to do it again correctly if needed.
Closes https://github.com/facebook/react-native/pull/16109
Differential Revision: D6017969
Pulled By: shergin
fbshipit-source-id: af37b831f1bb6206dabdaff36d4cb9e88fb1a496
7c89cf37c6