* ref: Inline onMucMemberLeft (has nothing to do with "moderator" and is broken).

* fix: Use isFocus instead of just reading the resource.

* ref: Inline onParticipantLeft.

* ref: Add _ to private function names.

* ref: Remove redundant function.

* ref: Initialize focusComponent once.

* ref: Remove two copies of "options".

* ref: Simplify the focusJid flow.

* ref: Rename focusCompoonent to targetJid.

* fix: Only retry on "invalid session" errors

We used to fire FOCUS_DISCONNECTED (which doesn't have anything to do
with anything disconnecting) and then retrying. This is not necessary
because FOCUS_DISCONNECTED is a fatal error and the client schedules
a reload of it's own (and we want the client reload as opposed to the
conference-request retry in case e.g. the shard has changed).

* ref: Remove use of visitorFocus.

* ref: Remove graceful shutdown handling (never used in backend).

* feat: Support conference request over HTTP.

* ref: eslint cleanup.

* fix: Add max timeout 2 minutes.

<conference xmlns="http://jitsi.org/protocol/focus" vnode="v1" ready="true" room="roomtest@conference.focus.exmaple.com" focusjid="focus@auth.meet.jitsi">
    <property name="authentication" value="false"/>
    <property name="sipGatewayEnabled" value="true"/>
</conference>

* Remove callstats conference property.

* Remove RTX conference property (removed from backend).

* Remove audioPacketDelay conference property (removed from backend).

<iq id='some-id' from='focus.exmaple.com' type='error' xml:lang='en-US' to='some-jid' xmlns='jabber:client'>
    <error type='modify'>
        <redirect xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/>
        <conference xmlns='http://jitsi.org/protocol/focus' vnode='v1' main-room='roomtest@conference.focus.exmaple.com' focusjid='focus@auth.meet.jitsi'/>
    </error>
</iq>

Avoid needing an external dependency.

We already log if a focus leaves, which the the important bit. This avoids a log
flood when leaving a large conference.

* feat: Make enableRemb signal client remb support.

* feat: Make enableTcc signal client tcc support.

* ref: Remove the enableOpusRed conference-wide option.

* ref: Remove the "enforcedBridge" option.

* ref: Remove pre-configured jigasi address.

The plan is to move the lastNLimits logic to bridge. The clients will be able to override(lower) the bridge limits through the bridge channel only. Also, this lets us configure last-n per receiver and not set the last-n value for the whole conference the way Jicofo sets it currently.

* Enable opus/red for the conference even when the browser doesn't support it.

* squash: Remove unused import

Pass a value for Opus' maxaveragebitrate parameter to Jicofo
iff opusMaxAvgBitrate is set as configuration option.

The LipSyncHack is currently broken in Jicofo and
will lead to unstable behavior.

Adds a flag which can be used to disable talking to Jicofo. It's
intended to be used only in jitsi-meet-spot which joins a special room.

In order to include browser capabilities in RTCBrowserType I needed to
refactor RTCBrowserType.

ESLint 4.8.0 discovers a lot of error related to formatting. While I
tried to fix as many of them as possible, a portion of them actually go
against our coding style. In such a case, I've disabled the indent rule
which effectively leaves it as it was before ESLint 4.8.0.

Because the implementation of LocalStorage in jitsi-meet at the time
of this writing is asynchronous with respect to loading and saving,
delay the generation of machineId in order to allow LocalStorage to
load any previously saved value.

Currently Jicofo does not include 'session-invalid' tag when there is
"machine ID" and "session ID" mismatch, but in such case the session-id
must be cleared as well. Otherwise we'll end up in an endless loop.

With JitsiAuthConnection the API consumer has to:
1. JitsiConference.createAuthenticationConnection,
2. JitsiAuthConnecition.authenticateAndUpgradeRole,
3. Wait on the Promise of 2,
4. Maybe cancel the JitsiAuthConnection of 1.

With authenticateAndUpgradeRole the API consumer has to:
1. JitsiConference.authenticateAndUpgradeRole,
2. Wait on the thenableWithCancel of 1.
3. Maybe cancel the thenableWithCancel of 1.

Some browsers may not support data channels (hi there, Edge!) and sometimes it
may not be desirable for other reasons.

Webpack 2 defines module.exports as a read-only property in ES6 modules.