SetOptions(), SetMaxBandwidth(), Set[Send|Recv]RtpHeaderExtensions(), Set[Send|Recv]Codecs() are now private. BUG=webrtc:4690 R=pbos@webrtc.org, pthatcher@webrtc.org Review URL: https://codereview.webrtc.org/1327933002 . Cr-Commit-Position: refs/heads/master@{#9973}