The vertical alignment was being set with javascript.
Recent changes might make the setting of alignment exit
early due to height 0 video. As position can be set
declaratively with css, use css to set position.

- simplify initialization procedure
- set user display name as the Etherpad name\
- use SharedDocumentButton

This adds an option to disable video autoplay that will be used mostly with maleus (our selenium-based load testing tool for testing the new bridge). Disabling video rendering lowers the resource utilisation of the selenium nodes.

This commit changes how the SmallVideo.isVideoPlayable method works.

1st we remove the check on the video stream muted field (materialized with the
!this.videoStream.isMuted() guard). This check is redundant as it is
already materialized in the !this.isVideoMuted check (the isVideoMuted
field is updated with the return value of the videoStream.isMuted()
method).

2nd we return false if we're in audio only mode, because it's
(obviously) undesirable to have a playable video when in audio only
mode.

Use the width of its container as the size, so the font icons can be rendered at
a good size.

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.

Multiple requests for checkUserRemoteControlSupport can be in
flight simultaneously. Order of promise resolution is not
guaranteed. It is possible for Request A and Request B to be
in flight and then Request B's promise chain resolves first.
Request A could have encountered errors and then resolve. Then
what could happen is checkUserRemoteControlSupport returns true
for remote control support due to Request B and the UI updates.
But then checkUserRemoteControlSupport returns false for
remote control support due to Request A's error and the UI
updates to hide remote control.

Undoes the logic added in:
ebcde745ef

* 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.

* Updates start silent, turning on startWithAudioMuted and few UI tweaks.

Disabled mic unmute button and removes remote participants volume slider.

* Adds analytics for start silent.

* Removes extra semi colon.

* Updates lib-jitsi-meet and updates meeting info text.

VideoLayout schedules a large video update by passing in
the video stream on the small video instance. When a stream
is removed, the UI is removed from the small video instance
but a reference to the stream is left. So when VideoLayout
schedules the large video update after a stream removal,
the old stream from the small video instance is re-used,
even though it has been removed.

This change also brings balance with RemoteVideo method
"addRemoteStreamElement" which sets the stream on the
small video instance, so now "removeRemoteStreamElement
unsets it.

- Use actions to notify the rest of the app that
  a mic or camera error has occurred
- Use middleware to respond to those notifications
  of errors by showing in-app notifications and
  notifying the external api

Stop using special case logic for aligning screenshare videos.
It may be possible to have positioning all done using CSS but that
seems to be a more significant refactoring.

Use subscribers to detect state change and emit those
out to other participants. Use middleware to register
the command listener.

When a fade in/out animation is in progress, another large
video update can be queued but can try to force itself onto
large video. For example a pin can be in progress and while
the fade in/out animation plays, local video can change its
video type during the animation and forcing an update of
large video. This results in local video getting forcible
updated onto large video while the pinned video is left on
small video only.

* ref(display-name): do not pass in display name

The component gets the state itself from redux.

* fix(display-name): do not default name to placeholder name

The web display name component supports inline editing of
the name. Problems can occur when the displayed name
differs from the actual saved name, because participants
without a display name, including the local user, have
a different, default display name displayed. So when
editing starts, the input field is populated with the
default name. To workaround such while supporting fetching
the display name using mapStateToProps, pass in both the
name which should be shown and the name value saved in
settings.

* ref(display-name): rename methods

* fix(large-video): do not show avatar if no url

By default the large video dominant speaker avatar
has an empty src, which will result in a broken
image displaying. There is also disconnect with
non-react code trying to set an undefined src.
To prevent such until local avatar generation
work is done in the future, just don't show the
avatar.

* fix(conference): set the room instance earlier

Set the room instance on APP.conference before triggering
a redux update of the conference being set,, because
middleware can then fire and call methods on APP.conference
that depend on the room being set.

* get local participant directly from store instead of from global

- Reset some state on the singletons conference
  and VideoLayout.
- Add a way for LocalVideo to clean itself up
  by sharing logic with the other SmallVideos.
- Add clearing of chat messages so they don't
  linger.
- Remove some UI event listeners.