message: Make ProcessArgMaxOperator faster by reserving the correct output dims.
diff: @@ -1501,7 +1501,7 @@ void ProcessArgMaxOperator(Model* model, ArgMaxOperator* op) {
  const std::vector<int>& input_dims = input_array.shape().dims();
  std::vector<int> output_dims;
  - output_dims.reserve(input_dims.size() - 1);
  + output_dims.reserve(input_dims.size());
  for (int i = 0; i < input_dims.size() - 1; ++i) {
  output_dims.push_back(input_dims[i]);
  }
  