Starting in Chrome 71, tracks without a stream are
given the msid "-", which in plan b incorrectly
triggers an onaddstream even with a default local
stream.

fix(docs): update url for loading lib

deps: update to webpack 4

fix(RTC): Pass options allowing GUM to work with config

This cleans up the method call, where some duplicate data was passed.

The 'options' identifier is used for different objects, which has lead to a bug where
the object that passes along the 'config.js' provided data is lost along the way. Code
that's further down the execution stack still expects to process that configuration,
which indicates that not passing it along is unintentional.

With this change, an Android device will adhere to the value defined in the 'resolution'
value of config.js, something it currently does not.

It's supported in Chrome >= 65.

* ignore duplicate jibri status updates

* re-add mistakenly removed return

fix(RTPStatsCollector): this.stop is 'undefined'

Until M69 Chrome used to consistently emit "onstreamadded" when
audio/video stream is added for the first time and then emit track
events only if the stream is modified afterwards (video track replaced).

However it looks like now it can first emit "onstreamadded" and then
additional "ontrackadded" for the MediaStreamTrack that was already
included in the MediaStream signalled by the "onstremadded" event. I
have not managed to figure out what is causing this and the only
difference in the SDP is the fact that the remote peer (JVB) includes
IPv6 candidates. Anyway it doesn't hurt to have such a safeguard.

The 'self.errorCallback' was passed incorrectly - it should have been
bound to 'self' eventually, but now the arrow function is the preferred
way.

Update to Babel 7 (needed for RN 0.57 update)

feat(BworserCapabilities): fix device change detection

Safari 11 has `navigator.mediaDevices.ondevicechange` but doesn't define
`navigator.mediaDevices.addEventListener`. 🤦

Fixes: https://github.com/jitsi/lib-jitsi-meet/issues/823

feat(TPC): fix handling layer suspension when RTPSender is not supported

Just skip it in such environments, such as React Native.

deps: js-utils

feat(flow): fix webpack bundling when Flow annotations are used

Refactor permissions

Share code amongst "Chrome-like" browsers

Use the W3C Permissions API where possible. At the time of this writing this is
supported in Chrome >= 64.

The code for handling device availability has been disabled for a long time,
plus it's ill named since it represents 2 abstractions: lack of permissions and
lack of devices.

Time for it to rest in the git graveyard.

We now use PeerConnection promise-based APIs, which were introduced in M51.

This function helps simplify the code when handling browsers that are pretty
much Chrome in disguise.

js-utils has some, so we need the preset or webpack fails with a syntax error.

* feat: Read the server region from Jingle and broadcast it with statistics.

* feat: Adds the bridge count to local "statistics", refactors conference-properties.

* fix: Emits the conference properties with the event, small fixes.

* ref: Orders the imports alphabetically.

As described by @virtuacoplenny:
[T]he ordering is based on import path, not import name, with different
file depths being grouped together, node modules being grouped together
at the top.

* fix: Keeps JitsiConference#properties always defined.

* fix: Does not fire an event when the argument is undefined.

Could not update karma-webpack to latest as it was not running because of an error:
The "path" argument must be of type string. Received type object
https://github.com/webpack-contrib/karma-webpack/issues/350

Chrome fires devicechange twice. This causes the DEVICE_LIST_CHANGED
event to fire twice. The listener in jitsi-meet has async logic
to handle the event, including creation of new tracks. So it
can happen that two devicechange events fire, the jitsi-meet
listener fires twice, creates duplicate tracks, and uses both
tracks. Diffing the device list for an actual change is a workaround
against extra devicechange events.

Note: this does not solve the issue in jitsi-meet of it not
handling quick successive DEVICE_LIST_CHANGED events.

This simple change helps to prevent `'The conference is has been already left'` error after kick. 
`Conference.leave` will detach chatRoom instance itself.

Keeps it consistent with the previous implementation.