Configure VoE NACK through AudioSendStream::Config.

webrtc/audio_send_stream.h

Index: webrtc/audio_send_stream.h
diff --git a/webrtc/audio_send_stream.h b/webrtc/audio_send_stream.h
index d8e98bb0ec9cff818c36d965e090076364eef333..045b8fd717488ddad8c017524180cb84b10eaf41 100644
--- a/webrtc/audio_send_stream.h
+++ b/webrtc/audio_send_stream.h
@@ -56,7 +56,7 @@ class AudioSendStream {
 
     std::string ToString() const;
 
-    // Receive-stream specific RTP settings.
+    // Send-stream specific RTP settings.
     struct Rtp {
       std::string ToString() const;
 
@@ -66,6 +66,9 @@ class AudioSendStream {
       // RTP header extensions used for the sent stream.
       std::vector<RtpExtension> extensions;
 
+      // See NackConfig for description.
+      NackConfig nack;
+
       // RTCP CNAME, see RFC 3550.
       std::string c_name;
     } rtp;