JitsiConnectionEvents.CONNECTION_FAILED with SERVER_ERROR will be
emitted when the XMPP connection is closed due too many 5xx HTTP errors.

Currently if RTCPeerConnection is closed (an event is delivered) and we haven't called close method ourselves, this means browser has closed it due to suspending the PC.

If Strophe drops the connection while not being asked to, it means that
most likely some serious error has occurred. One currently known case is
when a BOSH request fails for more than 4 times then the connection is
dropped without supplying a reason through the Strophe API
(the connection status simply goes to DISCONNECTED).

ICE connectivity issues can be transient and those should not prevent
from sending SSRC updates. XMPP stream is a separate connection/stream
and skipping the updates while ICE is disconnected results in broken
media session where the stream information is not propagated correctly
across the conference participants.

Introduce JingleSessionState constants. Make the invalid JingleSession
rejection an explicit action taken by the JitsiConference.

The corresponding extension's name was changed
in Jicofo to 'bridgeNotAvailable'.

The flag when set to 'true' will enforce ICE failure. It is supposed to
be used in automatic testing.

In case of roomPass is undefined, an error occurs: Cannot read property 'length' of undefined.

Our JSHint configuration is not extensive and we have excluded multiple
files from linting. Additionally, we have seen JSHint to be unable to
parse newer ECMAScript features such as the object spread operator
(proposal).

On the other hand, we have seen ESLint to beautifully work on React and
React Native source code in addition to ES2015 and later. Introduce
ESLint alongside JSHint as an intermediate step to eventually switching
from JSHint to ESLint.

As our source code does not fully follow even the JSHint rules we have,
it is very difficult to introduce ESLint with many rules. At the
beginning, introduce it with as little rules as possible. Morever,
ESLint is able to automatically fix certain rule offenders so once we
have ESLint merged we can incrementally add new rules while keeping our
commits' modification on as little subjects as possible.

When we receive kick presence it is both 110 and 307 status code, so we were triggering both conference_left and kicked event. Now when we receive kick we process as it is 110 to clean participants and room and then fire the kick event.

When only one participant is in the room and leaves(hangups) the only participant in members is focus.

Skips passing presence, cause it can reach the UI and there was a bug where we tried to pass the presence as an argument to the translation and ended in endless loop.

The places of the two arguments of the function createConnection were
switched in the function definition but the call to the function
remained unchanged.

Because the flag is required in the connection options anyway it will
be better to use it from one options set only to avoid redundancy.

The event is triggered when Jicofo sends 'session-terminate' and our
PeerConnection is closed.

Fix broken variable