Cherry picked from c9a94b0f in master. Do not merge.
Vladimir Chtchetkine authored
Implement CAMERA_MSG_PREVIEW_FRAME callback

Also does better work detecting pixel format for video frames, depending on the
mode that camera is intended to be operated with.

Change-Id: Idb2dfc7c0a79e81eff58f83a14af769afc713096
f7f68868