Add encoder/decoder names to software H264.

webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc

Index: webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc
diff --git a/webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc b/webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc
index c5141b3e253a3bba48f94e5e0f2207e2dfa5e055..bba30a3ca81acc368b9a13365f54ed06b1c94cd1 100644
--- a/webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc
+++ b/webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.cc
@@ -382,6 +382,10 @@ int32_t H264EncoderImpl::Encode(const VideoFrame& input_frame,
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
+const char* H264EncoderImpl::ImplementationName() const {
+  return "OpenH264";
+}
+
 bool H264EncoderImpl::IsInitialized() const {
   return openh264_encoder_ != nullptr;
 }