Remove deprecated AudioCodingModule::Destroy.

Have Channel hold a pointer rather than reference, and shorten the name.

TESTED=trybots
R=turaj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2256004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@4820 4adac7df-926f-26a2-2b94-8c16560cd09d
7 files changed