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-Commit-Position: refs/heads/master@{#9972}