Wire up transport sequence number / send time callbacks to webrtc via libjingle.

webrtc/video_engine/vie_channel_group.h

Index: webrtc/video_engine/vie_channel_group.h
diff --git a/webrtc/video_engine/vie_channel_group.h b/webrtc/video_engine/vie_channel_group.h
index e133d1a0b61a089174f160409a422b27b3473176..f1d73d7834cf62d56ee090f9c38ea20bf0e1f77b 100644
--- a/webrtc/video_engine/vie_channel_group.h
+++ b/webrtc/video_engine/vie_channel_group.h
@@ -77,6 +77,8 @@ class ChannelGroup : public BitrateObserver {
                         uint8_t fraction_loss,
                         int64_t rtt) override;
 
+  void OnSentPacket(const SentPacket& packet_sent);
+
  private:
   typedef std::map<int, ViEChannel*> ChannelMap;
   typedef std::map<int, ViEEncoder*> EncoderMap;