Added support in the AEC for refined filter adaptation.

webrtc/modules/audio_processing/aec/aec_core_internal.h

Index: webrtc/modules/audio_processing/aec/aec_core_internal.h
diff --git a/webrtc/modules/audio_processing/aec/aec_core_internal.h b/webrtc/modules/audio_processing/aec/aec_core_internal.h
index 05f5083c4ad919065048ec157456bfc6936c473a..b9a9a32f21e7ad1467f77ce1bbd3f71293fe5b92 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_internal.h
+++ b/webrtc/modules/audio_processing/aec/aec_core_internal.h
@@ -35,9 +35,8 @@ enum {
   kHistorySizeBlocks = 125
 };
 
-// Extended filter adaptation parameters.
+// Extended filter adaptation parameter.
 // TODO(ajm): No narrowband tuning yet.
-static const float kExtendedMu = 0.4f;
 static const float kExtendedErrorThreshold = 1.0e-6f;
 
 typedef struct PowerLevel {
@@ -130,7 +129,7 @@ struct AecCore {
   size_t num_bands;
   uint32_t seed;
 
-  float normal_mu;               // stepsize
+  float filter_step_size;        // stepsize
   float normal_error_threshold;  // error threshold
 
   int noiseEstCtr;
@@ -178,6 +177,7 @@ struct AecCore {
   int extended_filter_enabled;
   // 1 = next generation aec mode enabled, 0 = disabled.
   int aec3_enabled;
+  bool refined_adaptive_filter_enabled;
 
   // Runtime selection of number of filter partitions.
   int num_partitions;
@@ -211,7 +211,7 @@ typedef void (*WebRtcAecFilterFar)(
     float y_fft[2][PART_LEN1]);
 extern WebRtcAecFilterFar WebRtcAec_FilterFar;
 typedef void (*WebRtcAecScaleErrorSignal)(int extended_filter_enabled,
-                                          float normal_mu,
+                                          float mu,
                                           float normal_error_threshold,
                                           float x_pow[PART_LEN1],
                                           float ef[2][PART_LEN1]);