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

webrtc/p2p/base/p2ptransportchannel.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 236 matching lines @@
       this, &P2PTransportChannel::OnCandidatesAllocationDone);
   session->StartGettingPorts();
 }
 
 void P2PTransportChannel::AddConnection(Connection* connection) {
   connections_.push_back(connection);
   connection->set_remote_ice_mode(remote_ice_mode_);
   connection->set_receiving_timeout(receiving_timeout_);
   connection->SignalReadPacket.connect(
       this, &P2PTransportChannel::OnReadPacket);
+  connection->SignalSentPacket.connect(this,
+                                       &P2PTransportChannel::OnSentPacket);
   connection->SignalReadyToSend.connect(
       this, &P2PTransportChannel::OnReadyToSend);
   connection->SignalStateChange.connect(
       this, &P2PTransportChannel::OnConnectionStateChange);
   connection->SignalDestroyed.connect(
       this, &P2PTransportChannel::OnConnectionDestroyed);
   connection->SignalNominated.connect(this, &P2PTransportChannel::OnNominated);
   had_connection_ = true;
 }
 
@@ skipping 1068 matching lines @@
   SignalReadPacket(this, data, len, packet_time, 0);
 
   // May need to switch the sending connection based on the receiving media path
   // if this is the controlled side.
   if (ice_role_ == ICEROLE_CONTROLLED && !best_nominated_connection() &&
       connection->writable() && best_connection_ != connection) {
     SwitchBestConnectionTo(connection);
   }
 }
 
+void P2PTransportChannel::OnSentPacket(Connection* connection,
+                                       const rtc::SentPacket& packet_sent) {
+  ASSERT(worker_thread_ == rtc::Thread::Current());
+
+  // Do not deliver if packet doesn't belong to the correct transport channel.
+  if (!FindConnection(connection))

[pthatcher1, 2015/09/25 23:24:58]

I don't think this check is necessary.  And, do we really want to iterate
through all of the connections for every packet?

[stefan-webrtc, 2015/09/28 12:10:50]

I mostly did this to follow the convention in OnReadPacket(). Should I instead
check for connection == best_connection_ as in OnReadyToSend()? I assume there
are multiple connections for one P2PTransportChannel, but only one active?

[pthatcher1, 2015/09/28 23:58:40]

I don't really think the check in OnReadPacket is necessary either. But at least
in theory it's saying "if I remove a connection, stop receiving on it".  This
would be saying "if I remove a connection, stop telling me when things that I
asked to send are not sent", which doesn't sound as useful.

[stefan-webrtc, 2015/10/02 13:29:12]

No, that doesn't make a lot of sense. Fixing.

+    return;
+
+  SignalSentPacket(this, packet_sent);
+}
+
 void P2PTransportChannel::OnReadyToSend(Connection* connection) {
   if (connection == best_connection_ && writable()) {
     SignalReadyToSend(this);
   }
 }
 
 }  // namespace cricket