Added support for logging the SSRC corresponding to AudioPlayout events.

To do this, the logging of this event was moved from the ACM to
VoiceEngine Channel. A new LogAudioPlayoutEvent function was added on
the RtcEventLog interface, and the LogDebugEvent function was removed
since it is no longer being used.

BUG=webrtc:4741
R=henrik.lundin@webrtc.org, henrikg@webrtc.org, kwiberg@webrtc.org, stefan@webrtc.org, terelius@webrtc.org

Review URL: https://codereview.webrtc.org/1340283002 .

Cr-Original-Commit-Position: refs/heads/master@{#9972}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: ae856f2c9fc358e5cd68d8a595136dcef017ed96
9 files changed