Federico Trimboli 3d3edfc3da Replace magic numbers with safeAreaInsets in RCTDevLoadingView
Summary:
This PR replaces magic numbers used for offsetting `RCTDevLoadingView` when running on iPhone X, in favour of `safeAreaInsets`.

Tested on iPhone X and iPhone 8. Here is a screenshot showing how it looks on iPhone X.
![nansi](https://user-images.githubusercontent.com/3900360/39599961-b4239d90-4ef3-11e8-97f4-269d571a6c8d.png)
Closes https://github.com/facebook/react-native/pull/19119

Differential Revision: D7984823

Pulled By: hramos

fbshipit-source-id: 0c7c3ba0fa258a64f6c4a1e0620f87bf0620984c
2018-05-12 23:25:09 -07:00
..