GitLab

They will be moved to media in a future CL since they need to be used
from the audio service. A side-effect of this CL is that logs from the
SyncReader/Writer are prefixed with the stream_id, like other logs are.

Bug: 803102
Change-Id: Iae2876033e4172066d5a0a3b1322092f870dc32d
Reviewed-on: https://chromium-review.googlesource.com/878627Reviewed-by: Camille Lamy <clamy@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: Olga Sharonova <olka@chromium.org>
Commit-Queue: Max Morin <maxmorin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#531849}