Add missing functions and signatures for older OMX video libs compat

Nvidia OMX libs need these to work

AudioTrack: Do not inline getSessionId either

Should help for other nvomx versions that requires it.

Conflicts:
	include/media/AudioTrack.h
	media/libmedia/AudioTrack.cpp

Change-Id: I9f9afa844edf3e6d1fd25524f2cc155b974245ec
Merge "Add missing functions and signatures for older OMX video libs compat" into du44