This also changes the way frames are written in the WebM muxer. Now,
frames are stored and written on the next call to AddSample. So each
call to AddSample will write the previous frame. This is needed to
determine whether the given frame is the last one in the cluster.
Closes#70
Change-Id: Ic69ebad3c4729cdaa2017c9c7f497048501ac907
This does not support key-rotation and will give an error. This is
because WebM does not have a way to indicate a change in key ID using
media segments.
b/22463551
Change-Id: I9b3dac818dc370302a5afc0d25d8a060b64d30cd