Fixes an issue where immersive mode would be enabled when coming back from the
background on the welcome screen.
Re-fixes c57e713, which was not correct.
- Use 1 name for 1 abstraction. Instead of useFullScreen and enabled use
fullScreen.
- Comments are correct English sentences so no double spaces between
senteces, no capitalization of the work On midsentence.
- Write as little source code as possible if readability is preserved.
- Utilize Facebook's Flow.
- The name of a private function must start with _ and the jsdoc should
state that the function is private.
The implementation varies across platforms, with the same goal: allow the app to
use the entire screen real state while in a conference.
On Android we use immersive mode, which will hide the status and navigation bars.
https://developer.android.com/training/system-ui/immersive.html
On iOS the status bar is hidden, with a slide effect.