Base decision to send REMB on send codecs.

Fixes bug where Chromium would send REMB even though the remote party
doesn't announce support for it (because it was based on local codec
settings instead of remote ones).

BUG=4626
R=stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/54389004

Cr-Commit-Position: refs/heads/master@{#9170}
3 files changed