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 f5e7e3d0243fd16f2ad0cd0d1db898143372e711..c198ad2f8a5273ff20368149ada7f883bfbbfdef 100644
--- a/webrtc/video/send_statistics_proxy.cc
+++ b/webrtc/video/send_statistics_proxy.cc
@@ -161,6 +161,12 @@ void SendStatisticsProxy::SetContentType(
   }
 }
 
+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;