Also wires up target_enc_bitrate in WebRtcVideoEngine2. BUG=1667,1788 R=mflodman@webrtc.org, stefan@webrtc.org Review URL: https://webrtc-codereview.appspot.com/42479004 Cr-Commit-Position: refs/heads/master@{#8515} git-svn-id: http://webrtc.googlecode.com/svn/trunk@8515 4adac7df-926f-26a2-2b94-8c16560cd09d