Adding option to use mock or real objects instead of mocks.
This will help future testing efforts, where each test case can
select whether a mock or a real object should be used.
Adding new test InsertPacketsUntilBufferIsFull.
Removing a few uniteresting mock call warning.
R=turaj@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/9839004
git-svn-id: http://webrtc.googlecode.com/svn/trunk@5684 4adac7df-926f-26a2-2b94-8c16560cd09d