Fix regression where retransmission bitrate is no longer estimated.

BUG=1813
R=mflodman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1530004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@4095 4adac7df-926f-26a2-2b94-8c16560cd09d
3 files changed