brillo: Add tests to sweep audio parameters.

Add functionality to sweep over different parameters for sample rates,
widths, and channels for playback using OpenSL ES.

BUG=26747922,26746989,26746989
TEST=suite:brillo-audio passes

Change-Id: If96a022a0675fa7733cadcfb0ef3358beb9c1a95
Reviewed-on: https://chromium-review.googlesource.com/326485
Commit-Ready: Ralph Nathan <ralphnathan@chromium.org>
Tested-by: Ralph Nathan <ralphnathan@chromium.org>
Reviewed-by: Christopher Wiley <wiley@chromium.org>
3 files changed