stagefright: initial media_codecs_google*.xml files

Separated description of Google-provided codecs into their own
files based on domain.  Google-provided audio/telephony codecs
should be included prior to specifying vendor codecs.  Google-
provided video codecs should be included after vendor codecs.

Bug: 13549114
Change-Id: I216f01feaf0379c6cd7d8714e02792fdf2214a90