Transparency improvements in the echo canceller 3

webrtc/modules/audio_processing/aec3/subtractor_output.h

Index: webrtc/modules/audio_processing/aec3/subtractor_output.h
diff --git a/webrtc/modules/audio_processing/aec3/subtractor_output.h b/webrtc/modules/audio_processing/aec3/subtractor_output.h
index e2d23b5440f750aa4f31bcf2b99b22415ed736cc..87550475815369877f6fb1d58a02dd1a8267188a 100644
--- a/webrtc/modules/audio_processing/aec3/subtractor_output.h
+++ b/webrtc/modules/audio_processing/aec3/subtractor_output.h
@@ -20,6 +20,7 @@ namespace webrtc {
 
 // Stores the values being returned from the echo subtractor.
 struct SubtractorOutput {
+  std::array<float, kBlockSize> s_main;
   std::array<float, kBlockSize> e_main;
   std::array<float, kBlockSize> e_shadow;
   FftData E_main;
@@ -27,6 +28,7 @@ struct SubtractorOutput {
   std::array<float, kFftLengthBy2Plus1> E2_shadow;
 
   void Reset() {
+    s_main.fill(0.f);
     e_main.fill(0.f);
     e_shadow.fill(0.f);
     E_main.re.fill(0.f);