Add kwiberg@webrtc.org to watchlist for audio_coding and audio_processing

BUG=
R=tina.legrand@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/13559004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6310 4adac7df-926f-26a2-2b94-8c16560cd09d