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

webrtc/base/asynctcpsocket.cc

Index: webrtc/base/asynctcpsocket.cc
diff --git a/webrtc/base/asynctcpsocket.cc b/webrtc/base/asynctcpsocket.cc
index 66fd3f1e007cddac36b91f5c10bd1acc7bfe0f1b..8e83cd1ea28db85613bc1611113c9f6ea6f3c500 100644
--- a/webrtc/base/asynctcpsocket.cc
+++ b/webrtc/base/asynctcpsocket.cc
@@ -268,6 +268,9 @@ int AsyncTCPSocket::Send(const void *pv, size_t cb,
     return res;
   }
 
+  rtc::SentPacket sent_packet(options.packet_id, rtc::Time());
+  SignalSentPacket(this, sent_packet);
+
   // We claim to have sent the whole thing, even if we only sent partial
   return static_cast<int>(cb);
 }