Add QP stats for sent video streams to StatsReport.

webrtc/video/send_statistics_proxy_unittest.cc

Index: webrtc/video/send_statistics_proxy_unittest.cc
diff --git a/webrtc/video/send_statistics_proxy_unittest.cc b/webrtc/video/send_statistics_proxy_unittest.cc
index 8e6b7bcab3159e0c7e1566a1853bc002d88ba201..c422422604521e2c23cc95ec2d4f1284345a24b9 100644
--- a/webrtc/video/send_statistics_proxy_unittest.cc
+++ b/webrtc/video/send_statistics_proxy_unittest.cc
@@ -16,6 +16,7 @@
 #include <vector>
 
 #include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/test/histogram.h"
 
 namespace webrtc {
 
@@ -384,6 +385,50 @@ TEST_F(SendStatisticsProxyTest, ClearsResolutionFromInactiveSsrcs) {
   EXPECT_EQ(0, stats.substreams[config_.rtp.ssrcs[1]].height);
 }
 
+TEST_F(SendStatisticsProxyTest, Qp) {
+  const int kQpIdx0 = 21;
+  const int kQpIdx1 = 39;
+  EncodedImage encoded_image;
+
+  RTPVideoHeader rtp_video_header;
+  rtp_video_header.codec = kRtpVideoVp8;
+
+  rtp_video_header.simulcastIdx = 0;
+  encoded_image.qp_ = kQpIdx0;
+  statistics_proxy_->OnSendEncodedImage(encoded_image, &rtp_video_header);
+
+  rtp_video_header.simulcastIdx = 1;
+  encoded_image.qp_ = kQpIdx1;
+  statistics_proxy_->OnSendEncodedImage(encoded_image, &rtp_video_header);
+
+  VideoSendStream::Stats stats = statistics_proxy_->GetStats();
+  EXPECT_EQ(kQpIdx0, stats.substreams[config_.rtp.ssrcs[0]].qp);
+  EXPECT_EQ(kQpIdx1, stats.substreams[config_.rtp.ssrcs[1]].qp);
+}
+
+TEST_F(SendStatisticsProxyTest, VerifyQpHistogramStats_Vp8) {
+  test::ClearHistograms();
+  const int kMinRequiredSamples = 200;
+  const int kQpIdx0 = 21;
+  const int kQpIdx1 = 39;
+  EncodedImage encoded_image;
+
+  RTPVideoHeader rtp_video_header;
+  rtp_video_header.codec = kRtpVideoVp8;
+
+  for (int i = 0; i < kMinRequiredSamples; ++i) {
+    rtp_video_header.simulcastIdx = 0;
+    encoded_image.qp_ = kQpIdx0;
+    statistics_proxy_->OnSendEncodedImage(encoded_image, &rtp_video_header);
+    rtp_video_header.simulcastIdx = 1;
+    encoded_image.qp_ = kQpIdx1;
+    statistics_proxy_->OnSendEncodedImage(encoded_image, &rtp_video_header);
+  }
+  statistics_proxy_.reset();
+  EXPECT_EQ(2, test::NumHistogramSamples("WebRTC.Video.Encoded.Vp8.Qp"));
+  EXPECT_EQ(kQpIdx1, test::LastHistogramSample("WebRTC.Video.Encoded.Vp8.Qp"));
+}
+
 TEST_F(SendStatisticsProxyTest, ClearsBitratesFromInactiveSsrcs) {
   BitrateStatistics bitrate;
   bitrate.bitrate_bps = 42;