RTCMediaStreamTrackStats.framesSent collected by RTCStatsCollector.

BUG=webrtc:6757, chromium:659137, chromium:627816

Review-Url: https://codereview.webrtc.org/2606033002
Cr-Commit-Position: refs/heads/master@{#16188}
diff --git a/webrtc/api/rtcstatscollector_unittest.cc b/webrtc/api/rtcstatscollector_unittest.cc
index 83d9fc8..da5d41e 100644
--- a/webrtc/api/rtcstatscollector_unittest.cc
+++ b/webrtc/api/rtcstatscollector_unittest.cc
@@ -1521,12 +1521,14 @@
   video_sender_info_ssrc1.local_stats[0].ssrc = 1;
   video_sender_info_ssrc1.send_frame_width = 1234;
   video_sender_info_ssrc1.send_frame_height = 4321;
+  video_sender_info_ssrc1.frames_encoded = 11;
 
   cricket::VideoSenderInfo video_sender_info_ssrc2;
   video_sender_info_ssrc2.local_stats.push_back(cricket::SsrcSenderInfo());
   video_sender_info_ssrc2.local_stats[0].ssrc = 2;
   video_sender_info_ssrc2.send_frame_width = 4321;
   video_sender_info_ssrc2.send_frame_height = 1234;
+  video_sender_info_ssrc2.frames_encoded = 22;
 
   // Remote video track with values
   rtc::scoped_refptr<MediaStreamTrackInterface> remote_video_track_ssrc3 =
@@ -1598,6 +1600,7 @@
   expected_local_video_track_ssrc1.detached = false;
   expected_local_video_track_ssrc1.frame_width = 1234;
   expected_local_video_track_ssrc1.frame_height = 4321;
+  expected_local_video_track_ssrc1.frames_sent = 11;
   ASSERT_TRUE(report->Get(expected_local_video_track_ssrc1.id()));
   EXPECT_EQ(expected_local_video_track_ssrc1,
             report->Get(expected_local_video_track_ssrc1.id())->cast_to<
@@ -1612,6 +1615,7 @@
   expected_local_video_track_ssrc2.detached = false;
   expected_local_video_track_ssrc2.frame_width = 4321;
   expected_local_video_track_ssrc2.frame_height = 1234;
+  expected_local_video_track_ssrc2.frames_sent = 22;
   ASSERT_TRUE(report->Get(expected_local_video_track_ssrc2.id()));
   EXPECT_EQ(expected_local_video_track_ssrc2,
             report->Get(expected_local_video_track_ssrc2.id())->cast_to<