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

talk/media/webrtc/webrtcvideoengine2.cc

Index: talk/media/webrtc/webrtcvideoengine2.cc
diff --git a/talk/media/webrtc/webrtcvideoengine2.cc b/talk/media/webrtc/webrtcvideoengine2.cc
index 0ee1d7b85b576d0a964fd1b49523af71cf89187d..b242358511ef2b9973f89c1eeef8ed2c1de3a14d 100644
--- a/talk/media/webrtc/webrtcvideoengine2.cc
+++ b/talk/media/webrtc/webrtcvideoengine2.cc
@@ -561,6 +561,9 @@ WebRtcVideoEngine2::WebRtcVideoEngine2()
   rtp_header_extensions_.push_back(
       RtpHeaderExtension(kRtpVideoRotationHeaderExtension,
                          kRtpVideoRotationHeaderExtensionDefaultId));
+  rtp_header_extensions_.push_back(
+      RtpHeaderExtension(kRtpTransportSequenceNumberHeaderExtension,
+                         kRtpTransportSequenceNumberHeaderExtensionDefaultId));
 }
 
 WebRtcVideoEngine2::~WebRtcVideoEngine2() {
@@ -1475,6 +1478,13 @@ void WebRtcVideoChannel2::OnRtcpReceived(
   }
 }
 
+void WebRtcVideoChannel2::OnPacketSent(const rtc::SentPacket& packet_sent) {
+  webrtc::SentPacket webrtc_packet_sent(packet_sent.transport_sequence_number,
+                                        packet_sent.send_time_ms);
+
+  call_->OnSentPacket(webrtc_packet_sent);

[pthatcher1, 2015/09/25 23:24:57]

Why not just propogate from the TransportChannel to Call_ directly (maybe going
through BaseChannel)?  Why go through the MediaChannel?

[stefan-webrtc, 2015/09/28 12:10:49]

Hm, this is probably an artifact of my lack of overview of libjingle code. I
basically followed what was being done with OnReadyToSend().

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

Not your fault, but OnReadyToSend needs to be cleaned up.  It's not a very good
model for copying.  

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

Done.

+}
+
 void WebRtcVideoChannel2::OnReadyToSend(bool ready) {
   LOG(LS_VERBOSE) << "OnReadyToSend: " << (ready ? "Ready." : "Not ready.");
   call_->SignalNetworkState(ready ? webrtc::kNetworkUp : webrtc::kNetworkDown);