Add codec name to CodecSpecificInfo and get the codec name stats from there instead.

webrtc/modules/video_coding/generic_encoder.cc

Index: webrtc/modules/video_coding/generic_encoder.cc
diff --git a/webrtc/modules/video_coding/generic_encoder.cc b/webrtc/modules/video_coding/generic_encoder.cc
index 28eb10ada1f43c3a5dd092cfd9531320ded9257c..1e8362ef09c114093daaef33935bdb5cd1476111 100644
--- a/webrtc/modules/video_coding/generic_encoder.cc
+++ b/webrtc/modules/video_coding/generic_encoder.cc
@@ -77,11 +77,6 @@ int32_t VCMGenericEncoder::Encode(const VideoFrame& frame,
   return result;
 }
 
-const char* VCMGenericEncoder::ImplementationName() const {
-  RTC_DCHECK_RUNS_SERIALIZED(&race_checker_);
-  return encoder_->ImplementationName();
-}
-
 void VCMGenericEncoder::SetEncoderParameters(const EncoderParameters& params) {
   RTC_DCHECK_RUNS_SERIALIZED(&race_checker_);
   bool channel_parameters_have_changed;