Ever since https://github.com/facebook/react-native/pull/23674 landed it has
been possible to run timers in the background, assuming your app is allowed to
run in the background already, as is our case. So, stop using the library on
iOS, which will avoid creatring needless backgound tasks.

When you join a conference that needs an authenticated moderator, as a guest, Jitsi Meet will continuously try and connect to the meeting every 5 seconds. Avoid starting the native call integration more than once.

Fixes: https://github.com/jitsi/jitsi-meet/issues/6260

Despite running Android 8.1, they don't support Picture-in-Picture.

Up until now we relied on implicit loading of middlewares and reducers, through
having imports in each feature's index.js.

This leads to many complex import cycles which result in (sometimes) hard to fix
bugs in addition to (often) breaking mobile because a web-only feature gets
imported on mobile too, thanks to the implicit loading.

This PR changes that to make the process explicit. Both middlewares and reducers
are imported in a single place, the app entrypoint. They have been divided into
3 categories: any, web and native, which represent each of the platforms
  respectively.

Ideally no feature should have an index.js exporting actions, action types and
components, but that's a larger ordeal, so this is just the first step in
getting there. In order to both set example and avoid large cycles the app
feature has been refactored to not have an idex.js itself.

Move all polyfills to a standalone feature, which gets imported before anything
else in the mobile entrypoint. This guarantees that any further import sees the
polyfilled environment.

Fixes: https://github.com/jitsi/jitsi-meet/issues/6008

This has the side effect of showing the bottom navbar when the toolbox is open,
which is a nice thing since back is accessible.

Fallback to the non-ConnectionService case for any error. Also, handle errors
when registering the phone account; Pixel C devices throw UnsupportedException.

Some Samsung devices will fail to fully engage ConnectionService if no SIM card
was ever installed on the device. We could check for it, but it would require
the CALL_PHONE permission, which is not something we want to do, so fallback to
not using ConnectionService.

Some devices seem to have a bug in their Android versions and startCall fails
with SecurityError because the CALL_PHONE permissions is not granted. This is
not a requirement for self-managed connection services as per the official
documentation though:
https://developer.android.com/guide/topics/connectivity/telecom/selfManaged

Alas, connection services takes over audio device management too, so let's
handle the error and disable CS if we get SecurityError.

Currently only 2 options are implemented, mainly aimed at helping troubleshoot
audio related problems:

- Disable native call integration (it disables CallKit / ConnectionService)
- Disable P2P

- Remove network-activity "feature"
    - It wasn't in use
    - It relied on internal React Native components, bound to break anytime
- Show an infinite loading indicator
- Style it just like the LoadConfigOverlay
    - Since it kinda represents the opposite, an "unload" then SDK is done

In iOS 13 if the call is not unmuted when we report it to the system as started,
an action to unmute it is dispatched automagically. Thanks, Apple.

So, delay synchronizing the muted state until the conference is started (after
the join action). This creates a small window for de-synchronization, but it's
very short and it seems unavoidable.

This change is only applied to operating systems built by the fruit company in
Cupertino.

React Native doesn't define __filename nor __dirname so do it artisanally. In
addition, this helps with centralizing the configuration passed to loggers.

This commit refactors device selection (more heavily on iOS) to make it
consistent across platforms.

Due to its complexity I couldn't break out each step into separate commits,
apologies to the reviewer.

Changes made to device handling:

- speaker is always the default, regardless of the mode
- "Phone" shows as a selectable option, even in video call mode
- "Phone" is not displayed when wired headphones are present
- Shared device picker between iOS and Android
- Runtime device updates while the picker is open

This refactors all handling of audio-only and last N to 2 features in preparation
for "low bandwidth mode".

The main motivation to do this is that lastN is a "global" setting so it helps
to have all processing for it in a single place.

Moves getCurrentConferenceUrl method to base/connection to allow reuse.
The new location is not ideal, but looks the best based on the imports
required (trying to avoid circular dependencies).

The welcomePageEnabled and pictureInPictureEnabled props on mobile have been
converted to feature flags.

Co-authored-by: Pawel Domas <pawel.domas@jitsi.org>

Dear reader, I'm not proud at all of what you are about to read, but sometimes
life just gives you lemons, so enjoy some lemonade!

Joining a conference implies first creating the XMPP connection and then joining
the MUC. It's very possible the XMPP connection was made but there was no chance
for the conference to be created.

This patch fixes this case by artificially genrating a conference terminated
event in such case. In order to have all the necessary knowledge for this event
to be sent the connection now keeps track of the conference that runs it.

In addition, there is an even more obscure corner case: it's not impossible to
try to disconnect when there is not even a connection. This was fixed by
creating a fake disconnect event. Alas the location URL is lost at this point,
but it's better than nothing I guess.

🔥🔥🔥

Using anything non-serializable for action types is discouraged:
https://redux.js.org/faq/actions#actions

In fact, this is the Flow definition for dispatching actions:

declare export type DispatchAPI<A> = (action: A) => A;
declare export type Dispatch<A: { type: $Subtype<string> }> = DispatchAPI<A>;

Note how the `type` field is defined as a subtype of string, which Symbol isn’t.

Consolidate all failure cases into a single one: CONFERENCE_TERMINATED. If the
conference ended gracefully no error indicator will be present, otherwise there
will be.

The conference disconnection process is asynchronous which means there's
no guarantee that there will be CONFERENCE_LEFT event for the old
conference, before the next conference is joined. Because of that we can
end up with two simultaneous calls on the native side which is not
always supported. End the call on CONFERENCE_WILL_LEAVE to fix this
corner case.

If a new conference is joined and as a result the current one is terminated,
don't ever attempt to set the audio mode.

* feat(Android): implement ConnectionService

Adds basic integration with Android's ConnectionService by implementing
the outgoing call scenario.

* ref(callkit): rename _SET_CALLKIT_SUBSCRIPTIONS

* ref(callkit): move feature to call-integration directory

* feat(ConnectionService): synchronize video state

* ref(AudioMode): use ConnectionService on API >= 26

Not ready yet - few details left mentioned in the FIXMEs

* feat(ConnectionService): add debug logs

Adds logs to trace the calls.

* fix(ConnectionService): leaking ConnectionImpl instances

Turns out there is no callback fired back from the JavaScript side after
the disconnect or abort event is sent from the native. The connection
must be marked as disconnected and removed immediately.

* feat(ConnectionService): handle onCreateOutgoingConnectionFailed

* ref(ConnectionService): merge classes and move to the sdk package

* feat(CallIntegration): show Alert if outgoing call fails

* fix(ConnectionService): alternatively get call UUID from the account

Some Android flavours (or versions ?) do copy over extras to
the onCreateOutgoingConnectionFailed callback. But the call UUID is also
set as the PhoneAccount's label, so eventually it should be available
there.

* ref(ConnectionService): use call UUID as PhoneAccount ID.

The extra is not reliable on some custom Android flavours. It also makes
sense to use unique id for the account instead of the URL given that
it's created on the per call basis.

* fix(ConnectionService): abort the call when hold is requested

Turns out Android P can sometimes request HOLD even though there's no
HOLD capability added to the connection (what!?), so just abort the call
in that case.

* fix(ConnectionService): unregister account on call failure

Unregister the PhoneAccount onCreateOutgoingConnectionFailed. That's
before the ConnectionImpl instance is created which is normally
responsible for doing that.

* fix(AudioModeModule): make package private and run on the audio thread

* address other review comments

componentWillMount is a deprecated lifecycle method;
componentDidMount should be used to kick off things
like ajax. In the case of the _App hierarchy, a promise
chain is used to perform initialization, and it is
first started in the constructor by initializing
storage. However, by the time storage is initialized,
resolving the first promise, _App has already mounted.
So, move it all to the componentDidMount lifecycle.

Per react migration docs, initially fetching external data is
recommended to be done in componentDidMount.

For the most part the changes are taking the "static propTypes" declaration off
of components and declaring them as Flow types. Sometimes to support flow some
method signatures had to be added. There are some exceptions in which more had
to be done to tame the beast:
- AbstractVideoTrack: put in additional truthy checks for videoTrack.
- Video: add truthy checks for the _videoElement ref.
- shouldRenderVideoTrack function: Some component could pass null for the
  videoTrack argument and Flow wanted that called out explicitly.
- DisplayName: Add a truthy check for the input ref before acting on it.
- NumbersList: Move array checks inline for Flow to comprehend array methods
  could be called. Add type checks in the Object.entries loop as the value is
  assumed to be a mixed type by Flow.
- AbstractToolbarButton: add additional truthy check for passed in type.

When a call is tarted in audio only mode due to the switch on the welcome page,
the wrong audio mode was chosen.

Use react-native-fastimage, which uses 2 full-native image impleentations using
well known and mature (native) libraries.

This gets us rid of 2 libraries which were observerd as a source of bugs and
created trouble with dependencies: react-native-fetch-blob and
react-native-img-cache. They are also no longer well maintained.

It's a separate view (on the native side) and app (on the JavaScript side) so
applications can use it independently.

Co-authored-by: Shuai Li <sli@atlassian.com>
Co-authored-by: Pawel Domas <pawel.domas@jitsi.org>