This reduces the complexity of insert and find (by timestamp) from linear to logarithmic, which has a big impact on large frame lists. BUG=1726 TEST=trybots, vie_auto_test --automated R=mikhal@webrtc.org Review URL: https://webrtc-codereview.appspot.com/1561005 git-svn-id: http://webrtc.googlecode.com/svn/trunk@4127 4adac7df-926f-26a2-2b94-8c16560cd09d