This patchset adds media_buffer.cpp/h files that brings
MediaFrame class to isolate from the rest of the code
access to libav AVFrame structure and decrease include dependencies
on libav includes over our code.

Sub-classes for audio and video are also implemented.

Note: old VideoFrame (video_base) is now replaced by this framework.

Refs #66877

Change-Id: I3dfd49cec3356c67fff848fdfd4992f85be4d824