Eloi Bail authored Mar 20, 2015 and Guillaume Roguez committed Apr 21, 2015

Simple muting implementation per call and media, eg : audio, video.
When a media is muted, black frames are sent in case of video.
Null samples are sent in case of audio.

In order to enhance bandwidth saving, a re-invite could be done
in a next version to properly stop muted media processing.

Refs #66722
Refs #69846

Change-Id: I9f03a7de77a6df3a3396197b9d966004300ebfcc
Signed-off-by: Guillaume Roguez <guillaume.roguez@savoirfairelinux.com>