Pass time constant to bwe smoothing filter.

webrtc/voice_engine/channel_proxy.cc

Index: webrtc/voice_engine/channel_proxy.cc
diff --git a/webrtc/voice_engine/channel_proxy.cc b/webrtc/voice_engine/channel_proxy.cc
index bfd5b17b285f71cdd06e0600d07dec89a76a14c7..79d62489f235c1c2956b9d55a20e7acb780b66b1 100644
--- a/webrtc/voice_engine/channel_proxy.cc
+++ b/webrtc/voice_engine/channel_proxy.cc
@@ -146,9 +146,10 @@ bool ChannelProxy::SendTelephoneEventOutband(int event, int duration_ms) {
   return channel()->SendTelephoneEventOutband(event, duration_ms) == 0;
 }
 
-void ChannelProxy::SetBitrate(int bitrate_bps) {
+void ChannelProxy::SetBitrate(int bitrate_bps,
+                              rtc::Optional<int64_t> probing_interval_ms) {
   // May be called on different threads and needs to be handled by the channel.
-  channel()->SetBitRate(bitrate_bps);
+  channel()->SetBitRate(bitrate_bps, probing_interval_ms);
 }
 
 void ChannelProxy::SetSink(std::unique_ptr<AudioSinkInterface> sink) {