Add full stack test cases with a fake network pipe.

R=pbos@webrtc.org
BUG=1872

Review URL: https://webrtc-codereview.appspot.com/20889004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6634 4adac7df-926f-26a2-2b94-8c16560cd09d