`host` contains the hostname:port portion, whereas `hostname` is just the
hostname, not including the port.

When rendering using a for loop each child whould have a key prop.

This solves the issue of view clipping on Android, plus it seems to be the RN
convention unless the views are very large and memory hungry.

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.

It doesn't work properly and gives a very bad user experience. Disble it until
all underlying issues in react-native-webrtc are ironed out.

On RN we don't use the global APP object, so don't save the store there unless
it's defined, which is the case in the current web version. Also, check for
undefined explicitly, since a "if (!APP)" check will throw a ReferenceError.

The mobile app remembers the domain which hosted the last conference. If
the user specified a full URL first and specified a room name only the
second time, it was not obvious that the second conference would be
hosted on the domain of the first conference.

Looks like Android gets confused as to what surface to blit when we hide or
show toolbars. Setting a border on the container, seems to force the entire
area to blit properly.

Other attempted approaches, with no success:
- zIndex of -100
- width and height of 0
- opacity of 0 and setting 'disabled' on touch containers

This patch applies the workaround in the welcome page and conference containers.

Includes automatic recommended Xcode project file fixes.

Lib-jitsi-meet uses jQuery's .append method to manipulate Jingle. The
method in question invokes the getter and setter of Element.innerHTML.
Unfortunately, xmldom which we use in React Native to polyfill DOM does
not polyfill Element.innerHTML. So polyfill it ourselves.

Turns out React Native's timers (setTimeout / setInterval) don't run while the
app is in the background: https://github.com/facebook/react-native/issues/167

This patch replaces the global timer functions with those from the
react-native-background-timer package, which work in the background.

These timers won't magically make an application work in the background, but
they will run if an application already happens to run in the background. That's
our case while in a conference, so these timers will run, allowing XMPP pings to
be sent and the conference to stay up as long as the user desires.

On Android the status and navigation bars are shown again after coming back from
the background, so enter full-screen mode again if needed.

- 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.

When callstats is not configured hide the button.

Until we make a decision on access modifier hints and adopt a respective
coding style, consistency is king.