Replace ExtraCodecOptions with new Config class that supports multiple settings at once. R=niklas.enbom@webrtc.org Review URL: https://webrtc-codereview.appspot.com/1452004 git-svn-id: http://webrtc.googlecode.com/svn/trunk@4017 4adac7df-926f-26a2-2b94-8c16560cd09d