When in a conference, try to enter PiP when pressing the back button. If this is
not possible (because it's unsupported, not enabled, etc.) fall back to the
previous behavior of simply hanging up.

This PR changes the logic for connecting / disconnecting conferences. Instead of
doing it in mount / unmount events from the Conference component, it moves the
logic to the appNavigatee action.

This fixes a regression introduced in 774c5ecd when trying to make sure the
conference terminated event is always sent.

By moving the logic to appNavigate we no longer depend on side-effects for
connecting / disconnecting, and the code should be more maintainable moving
forward.

An improvement to this is the concept of sessions, which, while not tackled
here, was taken into consideration.

* Groups devices notifications by type audio/video.

* Fixes passing correct device array.

For the external api to fire update events out of the iframe, it
must first be initialized within the jitsi app. Any invocations
by the app to send updates events before initialization will
cause the api to swallow the events. The chosen fix is to
initialize the api earlier so the first update of app's redux
store fires update events that the api will also fire out of
the iframe.

This change will affect current behavior in that right now
the update event of the initial set of the avatar url is
blocked, but the change will make that event fire out of the
iframe.

Currently devices set through the api are stored
as ids, and not user selected. This can cause
other existing user selected devices to take
precedence over the devices passed into the api.

Method blur is not called. Method blur is called
internally only.

This reverts commit 890151fa72.

Empower the parent.

So mobile and web can share logic for grouping chat
messages by sender.

It was extracted from the RN core to a community maintained package.

* Skips setting undefined device id to sink in audio preview.

* Fallbacks to use labels for user selected devices.

* Fixes comment.

By making the container 100% height and position relative, that
would cause it to overlap any static-positioned  elements below it.
The 100% makes it so that any watermarks intended for the bottom
of the page show up on the bottom of the page. However, it's not
needed because watermark stylings already try to position the
watermarks at the bottom.

Co-authored-by: Pawel Domas <pawel.domas@jitsi.org>

* Fix detecting preferred audio output.

Fixes detecting when a new output device is found and we have stored user preference of using that device.

* Does not store which is the currently open device on save.

Does not save the currently opened device when saving settings dialog, this will be done once we successfully replace the tracks to use the new devices.

* Saves opened audio device after successfully changing it.

If we do it earlier _updateAudioDeviceId is using localAudio and can store wrong value.

* Adds notification for new non preferred devices.

A notification is shown which gives an option to the user to select and use the newly plugged devices.
Adding custom button and handler for the action to the notifications.

* Changes logic to search and handle all newly added devices from array.

* Moves some utility methods to features/base/devices.