Clean up audio-related utility functions to compute buffer sizes

Renames SelectSamplesPerPacket() to GetHighLatencyOutputBufferSize() and moves
it into audio_hardware.h, where its low-latency counterpart lies.

BUG=NONE
TEST=NONE


Review URL: http://codereview.chromium.org/9442005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@124981 0039d316-1c4b-4281-b951-d872f2087c98
8 files changed