message: Use real time in BiasAddGrad benchmarks
diff: @@ -34,6 +34,7 @@ static Graph* BiasAddGrad(int d0, int d1, int d2, int d3) {
  #define BM_BiasAddGradNHWC(N, W, H, C, DEVICE) \
  static void BM_BiasAddGradNHWC##_##N##_##H##_##W##_##C##_##DEVICE( \
  int iters) { \
  + testing::UseRealTime(); \
  testing::ItemsProcessed(static_cast<int64>(iters) * N * H * W * C); \
  test::Benchmark(#DEVICE, BiasAddGrad(N, H, W, C)).Run(iters); \
  } \
  