Add QP sum stats for received streams.

webrtc/video/receive_statistics_proxy_unittest.cc

Index: webrtc/video/receive_statistics_proxy_unittest.cc
diff --git a/webrtc/video/receive_statistics_proxy_unittest.cc b/webrtc/video/receive_statistics_proxy_unittest.cc
index d431bc4afbcacb72e68f765e6564546ede02980a..76ccced820c13de8848bc5372368de317d70a7fc 100644
--- a/webrtc/video/receive_statistics_proxy_unittest.cc
+++ b/webrtc/video/receive_statistics_proxy_unittest.cc
@@ -54,11 +54,26 @@ class ReceiveStatisticsProxyTest : public ::testing::Test {
 TEST_F(ReceiveStatisticsProxyTest, OnDecodedFrameIncreasesFramesDecoded) {
   EXPECT_EQ(0u, statistics_proxy_->GetStats().frames_decoded);
   for (uint32_t i = 1; i <= 3; ++i) {
-    statistics_proxy_->OnDecodedFrame();
+    statistics_proxy_->OnDecodedFrame(-1);
     EXPECT_EQ(i, statistics_proxy_->GetStats().frames_decoded);
   }
 }
 
+TEST_F(ReceiveStatisticsProxyTest, OnDecodedFrameIncreasesQpSum) {
+  EXPECT_EQ(rtc::Optional<uint64_t>(), statistics_proxy_->GetStats().qp_sum);
+  statistics_proxy_->OnDecodedFrame(3);
+  EXPECT_EQ(rtc::Optional<uint64_t>(3u), statistics_proxy_->GetStats().qp_sum);
+  statistics_proxy_->OnDecodedFrame(127);
+  EXPECT_EQ(rtc::Optional<uint64_t>(130u),
+            statistics_proxy_->GetStats().qp_sum);
+}
+
+TEST_F(ReceiveStatisticsProxyTest, OnDecodedFrameWithoutQpQpSumWontExist) {
+  EXPECT_EQ(rtc::Optional<uint64_t>(), statistics_proxy_->GetStats().qp_sum);
+  statistics_proxy_->OnDecodedFrame(-1);
+  EXPECT_EQ(rtc::Optional<uint64_t>(), statistics_proxy_->GetStats().qp_sum);
+}
+
 TEST_F(ReceiveStatisticsProxyTest, OnRenderedFrameIncreasesFramesRendered) {
   EXPECT_EQ(0u, statistics_proxy_->GetStats().frames_rendered);
   webrtc::VideoFrame frame(