Add NACK rate throttling for audio channels.

webrtc/test/call_test.h

Index: webrtc/test/call_test.h
diff --git a/webrtc/test/call_test.h b/webrtc/test/call_test.h
index d8019e55b8c39114a7dc36b0f1345dc3672460ae..ee61d98f98faf5a52d7cc2ad83a505714b04cdee 100644
--- a/webrtc/test/call_test.h
+++ b/webrtc/test/call_test.h
@@ -25,6 +25,10 @@ namespace webrtc {
 class VoEBase;
 class VoECodec;
 
+namespace voe {
+class ChannelProxy;
+}
+
 namespace test {
 
 class BaseTest;
@@ -89,6 +93,7 @@ class CallTest : public ::testing::Test {
   VideoSendStream* video_send_stream_;
   AudioSendStream::Config audio_send_config_;
   AudioSendStream* audio_send_stream_;
+  std::unique_ptr<voe::ChannelProxy> audio_send_channel_proxy_;
 
   std::unique_ptr<Call> receiver_call_;
   std::unique_ptr<PacketTransport> receive_transport_;