Wiring discard rate of audio FEC/RED packets up to StatsReport.

BUG=webrtc:7903

Change-Id: I0325725be354ab89cfce1d3564936fe5ff93d303
Reviewed-on: https://chromium-review.googlesource.com/559339
Reviewed-by: Tommi <tommi@webrtc.org>
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Commit-Queue: Minyue Li <minyue@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19560}
diff --git a/webrtc/audio/audio_receive_stream_unittest.cc b/webrtc/audio/audio_receive_stream_unittest.cc
index 9723ee6..0d58614 100644
--- a/webrtc/audio/audio_receive_stream_unittest.cc
+++ b/webrtc/audio/audio_receive_stream_unittest.cc
@@ -327,6 +327,8 @@
             stats.speech_expand_rate);
   EXPECT_EQ(Q14ToFloat(kNetworkStats.currentSecondaryDecodedRate),
             stats.secondary_decoded_rate);
+  EXPECT_EQ(Q14ToFloat(kNetworkStats.currentSecondaryDiscardedRate),
+            stats.secondary_discarded_rate);
   EXPECT_EQ(Q14ToFloat(kNetworkStats.currentAccelerateRate),
             stats.accelerate_rate);
   EXPECT_EQ(Q14ToFloat(kNetworkStats.currentPreemptiveRate),