ContentValues: improves documentation

This corrects and clarifies the documentation for ContentValues.

Change-Id: Iddf54da093e97c32da2568eab8802b1b2715303b
Signed-off-by: Steve Pomeroy <steve@staticfree.info>
MediaCodec: docs: Clarify that audio/mp4a-latm is plain AAC, not in LATM

The mime type name is unfortunate since it implies that the data
should be provided as a LATM bitstream, which it should not.

Change-Id: I3c997025342e3298729db2bfaeace9fcac001af9