RTCInboundRTPStreamStats's [fir/pli/nack]_count are collected for video.

Previously this was only collected for RTCOutboundRTPStreamStats video,
with no comment saying it was missing for Inbound. (nack_count should be
collected vor audio as well but this is currently not available - there
is already an existing comment about this in rtcstats_objects.h.)

BUG=chromium:657855, chromium:657854, chromium:627816

Review-Url: https://codereview.webrtc.org/2515293002
Cr-Commit-Position: refs/heads/master@{#15185}
diff --git a/webrtc/api/rtcstatscollector.cc b/webrtc/api/rtcstatscollector.cc
index fbc6dbc..b866b68 100644
--- a/webrtc/api/rtcstatscollector.cc
+++ b/webrtc/api/rtcstatscollector.cc
@@ -107,6 +107,7 @@
   track_stats->ended = (track.state() == MediaStreamTrackInterface::kEnded);
 }
 
+// Provides the media independent counters (both audio and video).
 void SetInboundRTPStreamStatsFromMediaReceiverInfo(
     const cricket::MediaReceiverInfo& media_receiver_info,
     RTCInboundRTPStreamStats* inbound_stats) {
@@ -126,23 +127,32 @@
 
 void SetInboundRTPStreamStatsFromVoiceReceiverInfo(
     const cricket::VoiceReceiverInfo& voice_receiver_info,
-    RTCInboundRTPStreamStats* inbound_stats) {
+    RTCInboundRTPStreamStats* inbound_audio) {
   SetInboundRTPStreamStatsFromMediaReceiverInfo(
-      voice_receiver_info, inbound_stats);
-  inbound_stats->media_type = "audio";
-  inbound_stats->jitter =
+      voice_receiver_info, inbound_audio);
+  inbound_audio->media_type = "audio";
+  inbound_audio->jitter =
       static_cast<double>(voice_receiver_info.jitter_ms) /
           rtc::kNumMillisecsPerSec;
+  // |fir_count|, |pli_count| and |sli_count| are only valid for video and are
+  // purposefully left undefined for audio.
 }
 
 void SetInboundRTPStreamStatsFromVideoReceiverInfo(
     const cricket::VideoReceiverInfo& video_receiver_info,
-    RTCInboundRTPStreamStats* inbound_stats) {
+    RTCInboundRTPStreamStats* inbound_video) {
   SetInboundRTPStreamStatsFromMediaReceiverInfo(
-      video_receiver_info, inbound_stats);
-  inbound_stats->media_type = "video";
+      video_receiver_info, inbound_video);
+  inbound_video->media_type = "video";
+  inbound_video->fir_count =
+      static_cast<uint32_t>(video_receiver_info.firs_sent);
+  inbound_video->pli_count =
+      static_cast<uint32_t>(video_receiver_info.plis_sent);
+  inbound_video->nack_count =
+      static_cast<uint32_t>(video_receiver_info.nacks_sent);
 }
 
+// Provides the media independent counters (both audio and video).
 void SetOutboundRTPStreamStatsFromMediaSenderInfo(
     const cricket::MediaSenderInfo& media_sender_info,
     RTCOutboundRTPStreamStats* outbound_stats) {
diff --git a/webrtc/api/rtcstatscollector_unittest.cc b/webrtc/api/rtcstatscollector_unittest.cc
index e032384..64e7e0a 100644
--- a/webrtc/api/rtcstatscollector_unittest.cc
+++ b/webrtc/api/rtcstatscollector_unittest.cc
@@ -1383,6 +1383,9 @@
   video_media_info.receivers[0].packets_rcvd = 2;
   video_media_info.receivers[0].bytes_rcvd = 3;
   video_media_info.receivers[0].fraction_lost = 4.5f;
+  video_media_info.receivers[0].firs_sent = 5;
+  video_media_info.receivers[0].plis_sent = 6;
+  video_media_info.receivers[0].nacks_sent = 7;
   EXPECT_CALL(*video_media_channel, GetStats(_))
       .WillOnce(DoAll(SetArgPointee<0>(video_media_info), Return(true)));
 
@@ -1404,23 +1407,26 @@
 
   rtc::scoped_refptr<const RTCStatsReport> report = GetStatsReport();
 
-  RTCInboundRTPStreamStats expected_audio(
+  RTCInboundRTPStreamStats expected_video(
       "RTCInboundRTPVideoStream_1", report->timestamp_us());
-  expected_audio.ssrc = "1";
-  expected_audio.is_remote = false;
-  expected_audio.media_type = "video";
-  expected_audio.transport_id = "RTCTransport_TransportName_" +
+  expected_video.ssrc = "1";
+  expected_video.is_remote = false;
+  expected_video.media_type = "video";
+  expected_video.transport_id = "RTCTransport_TransportName_" +
       rtc::ToString<>(cricket::ICE_CANDIDATE_COMPONENT_RTP);
-  expected_audio.packets_received = 2;
-  expected_audio.bytes_received = 3;
-  expected_audio.fraction_lost = 4.5;
+  expected_video.fir_count = 5;
+  expected_video.pli_count = 6;
+  expected_video.nack_count = 7;
+  expected_video.packets_received = 2;
+  expected_video.bytes_received = 3;
+  expected_video.fraction_lost = 4.5;
 
-  ASSERT(report->Get(expected_audio.id()));
-  const RTCInboundRTPStreamStats& audio = report->Get(
-      expected_audio.id())->cast_to<RTCInboundRTPStreamStats>();
-  EXPECT_EQ(audio, expected_audio);
+  ASSERT(report->Get(expected_video.id()));
+  const RTCInboundRTPStreamStats& video = report->Get(
+      expected_video.id())->cast_to<RTCInboundRTPStreamStats>();
+  EXPECT_EQ(video, expected_video);
 
-  EXPECT_TRUE(report->Get(*expected_audio.transport_id));
+  EXPECT_TRUE(report->Get(*expected_video.transport_id));
 }
 
 TEST_F(RTCStatsCollectorTest, CollectRTCOutboundRTPStreamStats_Audio) {