It's an evolution of audio-only mode, where we also allow for receiving a remote
screen-share.

Diving deeper: this basically sets last N to 1 or 0 depending on the
availability of a screen-share.

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.

Otherwise the participant will not have been added yet
to state so the participant name will not display in
the notification.

Also, use the helper function to get the display name for a participant.

* Updates kick showing who kicked us.

* Notify participants that someone was kicked.

* Shows notification to user who is remotely muted.

* Updates the notification type.

* Muted by notification for mobile.

* Moves code to react and adds the kick notifications to mobile.

* Updates lib-jitsi-meet.

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.

Updating react-native-fast-image brings a couple of interesting changes:

- onLoad is not called for cached images (reported and ignored upstream)
- load progress not working if component not displayed (on Android)

In order to fix this, a combination of 2 approaches was used:

- onLoadEnd / onError are used to detect if the image is loaded
- off-screen rendering is used on Android to get progress events

While implementing the above, yours truly noticed the complexity was increasing
way too much, so some extra refactoring was also performed:

- componentWillReceiveProps is dropped
- an auxiliary component (AvatarContent) is used for the actual content of the
  Avatar, with the former passing the key prop to the latter

Using the key prop ensures AvatarContent will be recreated if the URI changes,
which is not a bad idea anyway, since the new image needs to be downloaded.

Filmstrip remote thumbnails display under certain conditions, as
defined in filmstrip/functions.web.js. Previously the raw
participant count was used, which included fake participants.
Using the selector getParticipantCount excludes fake participants,
causing YouTube thumbnails to remain hidden in a 1-on-1 call.

It was moved to js-utils, so make use of it.

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.

The Image adds a fade effect without asking, so lets explicitly disable
it. More info here:
https://github.com/facebook/react-native/issues/10194

* [WEB] add UI for transcription

* add analytics event for button, do not use global APP object

* use props instead of state, use local conference to kick participant

* put imports in alphabetical order

* add translation for TranscribingLabel

* fix merge conflict

* add closed caption button

* purge OverFlowMenuItem which starts and stops Transcription

* readd closed caption icon and fix small issues due to purge

* delete unused icon in _font.scss

BaseApp does all the heavy-lifting related to creating the redux store,
navigation, and so on.

App currently handles URL props and actually triggering navigation based on
them.

Use it unless the connection is not ACTIVE. We don't really care if it's
recovering or whatever, if it's not active it has problems, so that's that.

This fixes a potential edge case in which the connection remains in RESTORING
state for some time.

Instead of keeping dominant speaker locally, get it from redux and be
updated when the dominant speaker changes. This is in an attempt to mimic
the video layout being reactified and connected to redux.

Try to use the getCurrentConference function wherever the indention is
to check for the current conference.

Makes sure that whenever a conference is left or switched, the local
participant's id will be equal to the default value.

The problem fixed by this commit is a situation where the local
participant may end up sharing the same ID with it's "ghost" when
rejoining a disconnected conference. The most important and easiest to
hit case is when the conference is left after the CONFERENCE_FAILED
event.

Another rare and harder to encounter in the real world issue is
where CONFERENCE_LEFT may come with the delay due to it's asynchronous
nature. The step by step scenario is as follows: trying to leave a
conference, but the network is not doing well, so it takes time,
requests are timing out. After getting back to the welcome page the
the CONFERENCE_LEFT has not arrived yet. The same conference is joined
again and the load config may timeout, but it will be read from the
cache. Now the network gets better and conference is joining which
results in our ghost participant added to the redux state. At this point
there's the root issue: two participants with the same id, because the
local one was neither cleared nor set to the new one yet
(PARTICIPANT_JOINED come, before CONFERENCE_JOINED where we adjust the
id). Then comes CONFERENCE_JOINED and we try to update our local id.
We're updating the ID of both ghost and local participant. It could be
also that the delayed CONFERENCE_LEFT comes for the old conference, but
it's too late and it would update the id for both participants.

The approach here reasons that the ID of the local participant
may be reset as soon as the local participant and, respectively, her ID
is no longer involved in a recoverable JitsiConference of interest to
the user and, consequently, the app.

Co-authored-by: Pawel Domas <pawel.domas@jitsi.org>
Co-authored-by: Lyubo Marinov <lmarinov@atlassian.com>

If the ID of a remote participant was the same as the ID of the local
participant (across multiple conferences), removing the remote
participant on PARTICIPANT_LEFT would remove the local participant.

Like the preceding commit "ref(base/conference): clear the 'conference'
field on WILL_LEAVE", this commit is part of the story how we are to
deal with conferences which take noticeable time to leave.

Like the preceding commit "ref(base/conference): clear the 'conference'
field on WILL_LEAVE", this commit is part of the story how we are to
deal with conferences which take noticeable time to leave.

If a leave is delayed and the leaving JitsiConference manages to sneak a
PARTICIPANT_JOINED in, it may create a remote participant who even
collides with the local participant.

With so many abstractions called conference, I'm not surprised I made a
mistake and my reviewer didn't catch it.

As we are transitioning from remote participants identified by ID alone
to an ID-conference pair, the subsequent commits "Protect against late
PARTICIPANT_JOINED" and "Refine PARTICIPANT_LEFT for ID collisions"
caught the error.