Create ACM2 instance when calling AudioCodingModule::Create

BUG=2996
R=turaj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/12079005

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5952 4adac7df-926f-26a2-2b94-8c16560cd09d
6 files changed