Fix mismatch between different NACK list lengths and packet buffers.

This is a second version of http://review.webrtc.org/1065006/ which passes the parameters via methods instead of via constructors.

BUG=1289

Review URL: https://webrtc-codereview.appspot.com/1065007

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@3456 4adac7df-926f-26a2-2b94-8c16560cd09d
36 files changed