message: Explain usage of shuffle layer
diff: @@ -950,6 +950,7 @@ Status Converter::RenameAndMarkOutputTensors(
  // TODO(tmorris): Remove this work-around once we use TRT's IIdentityLayer
  // in ConvertIdentity.
  if (tensorflow::str_util::StartsWith(tensor->getName(), kOutputPHName)) {
  + // Using shuffle layer for identity by not setting reshape or transpose.
  nvinfer1::IShuffleLayer* layer = network()->addShuffle(*tensor);
  TFTRT_RETURN_ERROR_IF_NULLPTR(
  layer, StrCat("Output Copy for ", tensor->getName()));
  