This CL changes the V4L2 decoder and encoder to use the Android Size
structure instead of the one copied from Chrome, the Chrome size.h file
is removed.

Bug: 155138142
Test: arc.VideoEncodeAccel.h264_192p_i420_vm
      arc.VideoDecodeAccel.h264_vm
Change-Id: I8f63e847d8cf4ffd33621706287a44c93a4864fd