Creating files for FreeBSD from Linux files in WebRTC

[Joe Nosay]

In trunk/webrtc/modules in the sub-directories of video_capture,
video_render and  audio_device need to have a directory named freebsd in
each. Both the linux and mac sub-directories reference the mixer, capture,
and other parts of the system. Which ports in audio and multimedia have
FreeBSD as a part of the source files- not patched- along with Linux and
possibly Mac? I should be able to start with basic files for each with
enough references to study with and compare.