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 97d1e171761dfcd9eb2a1a4724ffa24516a525d9..67e553e41b458b3ae87b288ecb827f7c72af6e46 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);
 }