Fold AudioEncoderMutable into AudioEncoder

webrtc/common_audio/vad/include/vad.h

Index: webrtc/common_audio/vad/include/vad.h
diff --git a/webrtc/common_audio/vad/include/vad.h b/webrtc/common_audio/vad/include/vad.h
index 1944f9dc5a8684d9243a377a872c9ca7611900cb..72c09492b343da4a32dc505467a3ed53d18ecb91 100644
--- a/webrtc/common_audio/vad/include/vad.h
+++ b/webrtc/common_audio/vad/include/vad.h
@@ -37,8 +37,12 @@ class Vad {
                                  size_t num_samples,
                                  int sample_rate_hz);
 
+  // Reset VAD state.
+  virtual void Reset();
+
  private:
   VadInst* handle_;
+  Aggressiveness aggressiveness_;
 };
 
 }  // namespace webrtc