Expose codec implementation names in stats.

webrtc/video/send_statistics_proxy.cc

Index: webrtc/video/send_statistics_proxy.cc
diff --git a/webrtc/video/send_statistics_proxy.cc b/webrtc/video/send_statistics_proxy.cc
index 5c2052a207868d9c6b2e5c7bd4e7edbb0a83d7e1..2d4efcb68cc3f00992ae1639396e4c0356431886 100644
--- a/webrtc/video/send_statistics_proxy.cc
+++ b/webrtc/video/send_statistics_proxy.cc
@@ -128,6 +128,12 @@ void SendStatisticsProxy::UpdateHistograms() {
   }
 }
 
+void SendStatisticsProxy::OnEncoderImplementationName(
+    const char* implementation_name) {
+  rtc::CritScope lock(&crit_);
+  stats_.encoder_implementation_name = implementation_name;
+}
+
 void SendStatisticsProxy::OnOutgoingRate(uint32_t framerate, uint32_t bitrate) {
   rtc::CritScope lock(&crit_);
   stats_.encode_frame_rate = framerate;