API level 22 is below 23 (aka Marshmallow), which included an overhaul in the
permissions system. React Native recommends 22 (it's the default when you create
a new app) and there have been reports when set higher [0] and [1].

This also fixes a critical bug, wherein Jitsi Meet wouldn't request permissions
for the camera and microphone.

Last, this change also allows us to get rid of the overlay checking code,
because it was only needed for API level 23 or higher.

[0]: https://github.com/facebook/react-native/pull/10479
[1]: https://github.com/facebook/react-native/issues/10587

Also expose this in the native SDKs.

Copy it from the main fonts directory instead.

Changing the props from native (Java) code was only added in 0.45, so add a
workaround until we get to updating our React Native dependency.

The current implementation doesn't use the API and Transport modules. This is
due to the fact that they are too tied to APP at the moment, which is web only.

Once API is refactored and moved into the Redux store this will be adjusted,
though it's unlikely that the lowest level React Native module (ExternalAPI)
changes drastically.

This commit also introduces a stopgap limitation of only allowing a single
instance for JitsiMeetView objects on both Android and iOS. React Native doesn't
really play well with having multiple instances of the same modules on the same
bridge, since they behave a bit like singletons. Even if we were to use multiple
bridges, some features depend on system-level global state, such as the
AVAudioSession mode or Android's immersive mode. Further attempts will be made
at lifting this limitation in the future, though.

Dames en heren, welcome to Jitsi Meet SDK for Android, the Jitsi Meet library
for Android.

The Jitsi Meet SDK encapsulates React Native and all the dependencies Jitsi
Meet has so other aopplications can integrate it easily.

Unlike iOS, creating "fat" libraries is not allways (if at all) possible on
Android, however, effort was put into making the integration as easy as
possible.

While React Native can be embedded in native applications, I don't think it was
designed to be embedded as part of an Android library, hidden away from the
application using it. This surfaced as a number of issues which had to be
addressed specifically due to our use-case:

- Activity lifecycle methods must be linked with the React Native engine, so the
  library provides wrapper methods.
- Custom fonts have to be manually added as assets, since the provided gradle
  script doesn't work properly in a library target.
- The RN packager has to be manually triggered since the gradle script will no
  longer do it for us.

At this stage, the Jitsi Meet application is just a small single activity
application which uses the Jitsi Meet SDK to create a single activity which
represents the entire application. Events and external conference handling are
forthcoming.

PS: Yours truly would like to add that it was a lot more fun to work on the iOS
side of things.

Some devices may give an error stating that INTERACT_ACROSS_USERS_FULL
permission is neeced. This permission can only be achieved by signing the
application with the same key as the system, which is never going to happen so
deal with it by catching any exceptions setting the mode may cause and failing
as gracefully as we can.

Ref:
http://stackoverflow.com/questions/34172575/audiomanager-setmode-securityexception-on-huawei-android-4

Now that Apple have approved build 1.3.204 for release in the App Store,
the short app version needs to be incremented; otherwise, no new builds
can be uploaded to TestFlight and, respectively, for release in the App
Store.

When the audio-only mode is enabled, turn on the proximity sensor to dim the
screen and disable touch controls when there is an object nearby.

Recent versions of the Android plugin for Gradle started to automatically
download the SDK build tools dependency if it is not installed already.
So it is no longer necessary to have the developer of the Android app
install the SDK build tools dependency in advance.

Now that Apple have approved build 1.2.199 for release in the App Store,
the short app version needs to be incremented; otherwise, no new builds
can be uploaded to TestFlight and, respectively, for release in the App
Store.

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.

- 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.

- Maximum of 80 characters per line.
- Group first and then sort in alphabetical order.
- Fields should begin with a lowercase letter.

This module chooses the most appropriate audio default based on the specified
mode.

Use a minimum SDK version of 19, that is Anroid 4.4 (KitKat) and a target SDK of
23, that is, Android 6.0 (Marshmallow).

Now that Apple have approved build 1.1.185 for release in the App Store,
the short app version needs to be incremented; otherwise, no new builds
can be uploaded to TestFlight and, respectively, for release in the App
Store.

Now that Apple have approved build 1.0.178 for release in the App Store,
the short app version needs to be incremented; otherwise, no new builds
can be uploaded to TestFlight and, respectively, for release in the App
Store.

The variables in gradle.properties can be overridden on command line like: -Pversion=1.

Bundle our custom icon font jitsi.ttf in the Android app (which we
already do for the iOS app).

Additionally, remove icon font files which are not in use.

As a step toward merging jitsi-meet-react with jitsi-meet to share as
much source code as possible between mobile and Web, merge the part of
jitsi-meet-react's source tree which supports mobile inside the
jitsi-meet source tree and leave jitsi-meet-react's Web support in the
source code revision history but don't have it in master anymore because
it's different from jitsi-meet's Web support. In other words, the two
projects are mechanically merged at the file level and don't really
share source code between mobile and Web.