Offline screenshare quality test, plus loopback.

BUG=4171
R=mflodman@webrtc.org, pbos@webrtc.org, stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/34109004

Cr-Commit-Position: refs/heads/master@{#8408}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8408 4adac7df-926f-26a2-2b94-8c16560cd09d
17 files changed