For VGA (640x360), currently 1 thread is used.  This change increases it to 2 threads.  For HD, 4 threads are enabled. BUG=none TEST=run a hangout and screencast high framerate, high resolution windows of youtube.  Observe that 1 cpu is insufficient to maintain high framerate with complex content. Review URL: https://webrtc-codereview.appspot.com/1203006
For VGA (640x360), currently 1 thread is used.  This change increases it to 2 threads.  For HD, 4 threads are enabled.
BUG=none
TEST=run a hangout and screencast high framerate, high resolution windows of youtube.  Observe that 1 cpu is insufficient to maintain high framerate with complex content.
Review URL: https://webrtc-codereview.appspot.com/1203006

git-svn-id: 917f5d3ca488f358c4d40eaec14422cf392ccec9@3747 4adac7df-926f-26a2-2b94-8c16560cd09d

TimothyGu/libilbc,TimothyGu/libilbc,mwgoldsmith/ilbc,mwgoldsmith/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,mwgoldsmith/ilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,mwgoldsmith/libilbc,mwgoldsmith/libilbc,mwgoldsmith/ilbc,TimothyGu/libilbc,mwgoldsmith/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,mwgoldsmith/ilbc