Add statistics gathering for packet loss.

webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
index a79774d16029a0f992d111f2cb95e9ac0dde1f0a..0f1777ae2a1adc68f517691e66c74f8b97589286 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
@@ -611,6 +611,27 @@ void ModuleRtpRtcpImpl::GetSendStreamDataCounters(
   rtp_sender_.GetDataCounters(rtp_counters, rtx_counters);
 }
 
+void ModuleRtpRtcpImpl::GetRtpPacketLossStats(
+    struct RtpPacketLossStats* incoming_loss,
+    struct RtpPacketLossStats* outgoing_loss) const {
+  if (incoming_loss) {
+    incoming_loss->single_packet_loss_count =
+        receive_loss_stats_.GetSingleLossCount();
+    incoming_loss->multiple_packet_loss_event_count =
+        receive_loss_stats_.GetMultipleLossEventCount();
+    incoming_loss->multiple_packet_loss_packet_count =
+        receive_loss_stats_.GetMultipleLossPacketCount();
+  }
+  if (outgoing_loss) {
+    outgoing_loss->single_packet_loss_count =
+        send_loss_stats_.GetSingleLossCount();
+    outgoing_loss->multiple_packet_loss_event_count =
+        send_loss_stats_.GetMultipleLossEventCount();
+    outgoing_loss->multiple_packet_loss_packet_count =
+        send_loss_stats_.GetMultipleLossPacketCount();
+  }
+}
+
 int32_t ModuleRtpRtcpImpl::RemoteRTCPStat(RTCPSenderInfo* sender_info) {
   return rtcp_receiver_.SenderInfoReceived(sender_info);
 }
@@ -684,6 +705,9 @@ int ModuleRtpRtcpImpl::SetSelectiveRetransmissions(uint8_t settings) {
 // Send a Negative acknowledgment packet.
 int32_t ModuleRtpRtcpImpl::SendNACK(const uint16_t* nack_list,
                                     const uint16_t size) {
+  for (int i = 0; i < size; ++i) {
+    receive_loss_stats_.AddLostPacket(nack_list[i]);
+  }
   uint16_t nack_length = size;
   uint16_t start_id = 0;
   int64_t now = clock_->TimeInMilliseconds();
@@ -899,6 +923,9 @@ bool ModuleRtpRtcpImpl::SendTimeOfXrRrReport(
 
 void ModuleRtpRtcpImpl::OnReceivedNACK(
     const std::list<uint16_t>& nack_sequence_numbers) {
+  for (uint16_t nack_sequence_number : nack_sequence_numbers) {
+    send_loss_stats_.AddLostPacket(nack_sequence_number);
+  }
   if (!rtp_sender_.StorePackets() ||
       nack_sequence_numbers.size() == 0) {
     return;