Added basic framework for AEC3 in the audio processing module

webrtc/modules/audio_processing/audio_processing_impl.h

Index: webrtc/modules/audio_processing/audio_processing_impl.h
diff --git a/webrtc/modules/audio_processing/audio_processing_impl.h b/webrtc/modules/audio_processing/audio_processing_impl.h
index 0375a2532813de083c668f7ba2ab2e8e9b5c8b18..ae4d89b131c33fe9120a26cf94c8c808aa1a6f26 100644
--- a/webrtc/modules/audio_processing/audio_processing_impl.h
+++ b/webrtc/modules/audio_processing/audio_processing_impl.h
@@ -168,6 +168,7 @@ class AudioProcessingImpl : public AudioProcessing {
                 bool beamformer_enabled,
                 bool adaptive_gain_controller_enabled,
                 bool level_controller_enabled,
+                bool echo_canceller3_enabled,
                 bool voice_activity_detector_enabled,
                 bool level_estimator_enabled,
                 bool transient_suppressor_enabled);
@@ -186,6 +187,7 @@ class AudioProcessingImpl : public AudioProcessing {
     bool beamformer_enabled_ = false;
     bool adaptive_gain_controller_enabled_ = false;
     bool level_controller_enabled_ = false;
+    bool echo_canceller3_enabled_ = false;
     bool level_estimator_enabled_ = false;
     bool voice_activity_detector_enabled_ = false;
     bool transient_suppressor_enabled_ = false;
@@ -251,6 +253,7 @@ class AudioProcessingImpl : public AudioProcessing {
   void InitializeResidualEchoDetector()
       EXCLUSIVE_LOCKS_REQUIRED(crit_render_, crit_capture_);
   void InitializeLowCutFilter() EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
+  void InitializeEchoCanceller3() EXCLUSIVE_LOCKS_REQUIRED(crit_capture_);
 
   void EmptyQueuedRenderAudio();
   void AllocateRenderQueue()
@@ -382,6 +385,7 @@ class AudioProcessingImpl : public AudioProcessing {
     bool beamformer_enabled;
     bool intelligibility_enabled;
     bool level_controller_enabled = false;
+    bool echo_canceller3_enabled = false;
   } capture_nonlocked_;
 
   struct ApmRenderState {