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 2f0634043dbb9ec3bfb441c89421f6bc21835f94..29c94f1c9e71104353abee5e6f702acf0d848413 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() {
@@ -1662,12 +1665,14 @@ bool WebRtcVideoChannel2::SendRtp(const uint8_t* data,
                                   size_t len,
                                   const webrtc::PacketOptions& options) {
   rtc::Buffer packet(data, len, kMaxRtpPacketLen);
-  return MediaChannel::SendPacket(&packet);
+  rtc::PacketOptions rtc_options;
+  rtc_options.packet_id = options.packet_id;
+  return MediaChannel::SendPacket(&packet, rtc_options);
 }
 
 bool WebRtcVideoChannel2::SendRtcp(const uint8_t* data, size_t len) {
   rtc::Buffer packet(data, len, kMaxRtpPacketLen);
-  return MediaChannel::SendRtcp(&packet);
+  return MediaChannel::SendRtcp(&packet, rtc::PacketOptions());
 }
 
 void WebRtcVideoChannel2::StartAllSendStreams() {