Jicofo sends a presence when the audio/video sender limit is reaced in the conference. The client can then proceed to disable the audio and video mute buttons when this occurs.

They are companion rooms created in a separate MUC. The room relationship is
maintained by a Prosody plugin.

All signalling happens through the breakout rooms MUC component.
Co-authored-by: Saúl Ibarra Corretgé <saghul@jitsi.org>

...to advertise track's muted state and the video type.

For now, if the source name signaling flag is enabled, both legacy and
new <SourceInfo> element will be used at the same time. This is to be
able to interoperate with legacy clients and start testing the new
format at the same time. Whenever possible <SourceInfo> will be used
as main source of truth with the fallback to legacy <audiomuted/>,
<videomuted/> and <videotype/> elements.

* feat: Adds to JitsiConferenceEvents CONFERENCE_JOIN_IN_PROGRESS.

* squash: Fixes tests.

ChatRoom.setAudioMute and ChatRoom.setVideoMute are
not async, so no callbacks nor promises are necessary.

* fix(xmpp): use text parameter instead of attr for message

bug: msg with elementName != 'body' ->
   Cannot read property 'appendChild' of null

fix leads to another problem - there is some magic in the 'c' function:
"This function moves the current element pointer to the child,
unless text is provided"

apply the same magic here. will be removed in the next commit

* fix(xmpp): do not rely on internals of Strophe.c

* squash: Fixes tests.

Co-authored-by: damencho <damencho@jitsi.org>

* feat: Audio/Video moderation.

* squash: Fix docs.

* squash: Adds some warning logs when execution is rejected.

* squash: Changes a field name in the message for adding jid to whitelist.

* squash: Send to participants only message about approval.

Skips sending the whole list.

* squash: Fixes tests.

* squash: Adds more logs.

* feat: Separates enable/disable by media type.

Adds actor to the messages to inform who enabled it.

* squash: Fixes log line.

* squash: Fixes comments.

* squash: Fixes log messages.

* squash: Fixes comments.

* feat: Video type camera is default value of missing, skip it in presence.

We skip sending initial video type camera if it is already missing from presence, if it changes we send the last value.
We also are dropping the namespace as it is not used anywhere and just increases presence size.

* feat: A/V muted is default so we can skip adding it initially to the presence.

Dropping the namespace as it is not used anywhere and that reduces size.

* squash: Drops unused setting.

* squash: Adds a config option to enable skipping the muted state.

* fix: Adds back removed method used by jibri.

It was removed by https://github.com/jitsi/lib-jitsi-meet/pull/1512.

* squash: Adds a deprecated note.

* Added video mute participant

* Trigger mute event

* Optimized mute type checks

* Fixed event name

* Fixed some linter issues

* Fixed more linter issues

* And even more linter issues fixed

* And more linter fixes

* Added media type to analytics event

Determine the preferred codec for a given endpoint based on the config.js settings and the codecs supported by the endpoint.
The preferred codec is published in presence and then used by the other endpoints in the call during join/leave to determine
if the codec needs to be changed on the fly. Different codecs can be configuered for p2p/jvb connections.
The preferredCodec/disabledCodec settings under videoQuality will have precedence over the older settins like preferH264/disableH264.

* fix: Drops unused parameter of join and sendPresence.

* feat: Skips using disco-info for features.

Uses presence to publish features added externally.
Recognizes jigasi participants using a specific presence extension used by jigasi.

* squash: Fixes tests.

* squash: Adds e2ee to the features in presence.

* squash: Fix function name and docs.

* squash: Drops detecting jigasi from initiator.

Using the newly added presence features.

* squash: Drops unused var.

* squash: Fix comments.

* squash: Adds a constant and for E2EEE feature.

If ICE fails will set the special request restart attribute
in the 'session-terminate' sent to Jicofo in order to restart
the Jingle session.

Used for extending owner privileges to other participants in the chat room.

* Initial impl of lobby rooms.

* Fixes tests to check the new fulljid added to MUC_MEMBER_JOINED.

* Updates few of the comments, renaming some functions.

* Renames disableLobby ChatRoom option to enableLobby.

* Fixes a comment.

* Moves setMembersOnly method to ChatRoom.

* Fixes counting members, to exclude jicofo.

* Moves setLobbyRoomJid earlier and renames a method.

Rename _maybeEnableDisable to maybeJoinLeaveLobbyRoom.

* Drops using custom roomconfig lobbypassword field and reuse room lock.

* Handles destroying the lobby room.

* Handles clear lobby room on destroy for moderators.

We do not try to leave the lobby room as it is server-side destroyed and we handle that. The only case of leaving a lobby room is when request to join room is being approved.

* Join main room if lobby is disabled while waiting.

* Adds MEMBERS_ONLY_CHANGED conference event.

* fix: Make sure we leave lobby if main room is joined.

* fix: Setting password when joining locked room.

* fix: Fixes case where we enable lobby for already locked room.

* fix: Fixes case where we enable lobby and then lock room.

* fix: Fixes lint.

* ref: Removes shared password for lobby.

This functionality is handled by the lock room password and handled there.
Removes duplication and unnecessary complicated API for lobby room.

* fix: Fixes comments.

* fix: Skips sending an extra presence on join.

* Renames the variable names.

This has become obsolete thanks to ES6 arrow functions

When modifying the room protection (setting or unsetting a password), the muc#roomconfig_passwordprotectedroom should always be defined. This fixes issue #512.

Send conference.join event only after the peer connection is created.
This way we won't send events for lonely calls.

All calls to connection.send should go through the wrapper in order to
prevent breaking the connection by calling it in the not connected
state.

This prevents from accessing Strophe internals directly and allows to
block 'send' calls while disconnected. The latter breaks the stream
resume logic by putting stanzas onto the send queue.

TODO make jitsi strophe plugins use the XmppConnection wrapper whenever
possible instead of interacting with the Strophe.Connection directly.

Attempts to fix the following issue:
1. Electron user starts the conference join process.
2. Electron user adds remote control capability and
   attempts to send presence.
3. Electron user presence send is blocked because the
   conference has not been joined.
4. Electron user joins the conference.
5. The remote control capability is not emitted until
   some other presence change triggers another
   presence send. Until then, other uses will not see
   remote control option available for the electron
   user.