Removed callback between old AudioConferenceMixer and OutputMixer. The audio frame with mixed audio…

webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h

Index: webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h
diff --git a/webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h b/webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h
index f6916409536d5a86e459255f7afcf41122efb7e6..e95d86843ae36799eb2d47fd97f86b669d41fdf8 100644
--- a/webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h
+++ b/webrtc/modules/audio_mixer/include/new_audio_conference_mixer.h
@@ -16,9 +16,7 @@
 #include "webrtc/modules/include/module_common_types.h"
 
 namespace webrtc {
-class OldAudioMixerOutputReceiver;
 class MixerAudioSource;
-class Trace;
 
 class NewAudioConferenceMixer : public Module {
  public:
@@ -40,11 +38,6 @@ class NewAudioConferenceMixer : public Module {
   int64_t TimeUntilNextProcess() override = 0;
   void Process() override = 0;
 
-  // Register/unregister a callback class for receiving the mixed audio.
-  virtual int32_t RegisterMixedStreamCallback(
-      OldAudioMixerOutputReceiver* receiver) = 0;
-  virtual int32_t UnRegisterMixedStreamCallback() = 0;
-
   // Add/remove participants as candidates for mixing.
   virtual int32_t SetMixabilityStatus(MixerAudioSource* participant,
                                       bool mixable) = 0;
@@ -61,6 +54,10 @@ class NewAudioConferenceMixer : public Module {
   virtual bool AnonymousMixabilityStatus(
       const MixerAudioSource& participant) const = 0;
 
+  // Performs mixing by asking registered participants for audio.
+  // The mixed result is placed in the provided AudioFrame.
+  virtual void Mix(AudioFrame* audio_frame_for_mixing) = 0;
+
   // Set the minimum sampling frequency at which to mix. The mixing algorithm
   // may still choose to mix at a higher samling frequency to avoid
   // downsampling of audio contributing to the mixed audio.