This is the counterpart of CallParticipantModel for the local
participant. For now it just stores whether audio and video are enabled
or not, and whether the local participant is speaking or not, but it
will be eventually extended with further properties.
It is also expected that the views, like the button with the microphone
state, will update themselves based on the model. Similarly the model
should be moved from the CallActivity to a class similar to
CallParticipant but for the local participant. In any case, all that is
something for the future; the immediate use of the model will be to know
when the local state changes to notify other participants.
Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>
