Move video_coding to new Clock interface and remove fake clock implementations from RTP module tests.

TEST=video_coding_unittests, video_coding_integrationtests, rtp_rtcp_unittests, trybots

Review URL: https://webrtc-codereview.appspot.com/1044004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@3393 4adac7df-926f-26a2-2b94-8c16560cd09d
67 files changed