GitLab

Split GetPreferredAudioParameters functions to improve readability,
move helper functions to unnamed namespace, fix typo.

R=maxmorin@chromium.org, olka@chromium.org

Bug: 774998
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I630e02dc73152eaf662a94ef0e1a4150a8ebcec9
Reviewed-on: https://chromium-review.googlesource.com/743361Reviewed-by: Olga Sharonova <olka@chromium.org>
Reviewed-by: Max Morin <maxmorin@chromium.org>
Commit-Queue: Marina Ciocea <marinaciocea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512794}