Hooked up RtcEventLog. It lives in Voice Engine and pointers are propagated to ACM and Call.

webrtc/modules/audio_coding/main/interface/audio_coding_module.h

Index: webrtc/modules/audio_coding/main/interface/audio_coding_module.h
diff --git a/webrtc/modules/audio_coding/main/interface/audio_coding_module.h b/webrtc/modules/audio_coding/main/interface/audio_coding_module.h
index b7d9a91b2f8dcaa3c7355a0d65b3c0653532f728..55e11600497fe30f74b6bd77746be3db20db8bed 100644
--- a/webrtc/modules/audio_coding/main/interface/audio_coding_module.h
+++ b/webrtc/modules/audio_coding/main/interface/audio_coding_module.h
@@ -26,9 +26,10 @@ namespace webrtc {
 // forward declarations
 struct CodecInst;
 struct WebRtcRTPHeader;
+class AudioEncoderMutable;
 class AudioFrame;
+class RtcEventLog;
 class RTPFragmentationHeader;
-class AudioEncoderMutable;
 
 #define WEBRTC_10MS_PCM_AUDIO 960  // 16 bits super wideband 48 kHz
 
@@ -978,6 +979,19 @@ class AudioCodingModule {
   // Disable NACK.
   virtual void DisableNack() = 0;
 
+  ///////////////////////////////////////////////////////////////////////////
+  // void SetEventLog(RtcEventLog* event_log)
+  //
+  // Sets an RtcEventLog object to enable logging of debug events inside the
+  // audio coding module. Calling this function is optional, if no logging
+  // object is set then no ACM events will be recorded in the event log.
+  // It is allowed to call this function with a nullptr to disable any logging
+  // activity.
+  //
+  // Input:
+  //   -event_log         : pointer to logging object.
+  virtual void SetEventLog(RtcEventLog* event_log) = 0;
+
   //
   // Get a list of packets to be retransmitted. |round_trip_time_ms| is an
   // estimate of the round-trip-time (in milliseconds). Missing packets which