message: BufferDataset changes for v2
  Summary: Ref T14799
  Test Plan: BufferDataset passing.
  Reviewers: #tensorflow, davidn
  Maniphest Tasks: T14799
diff: @@ -121,6 +121,11 @@ class BufferDatasetOp::Dataset : public DatasetBase {
  return dataset()->input_->MakeIterator(ctx, prefix(), &input_impl_);
  }
  + string BuildTraceMeName() override {
  + return strings::StrCat(prefix(), "#buffer_size=", dataset()->buffer_size_,
  + "#");
  + }
  +
  Status GetNextInternal(IteratorContext* ctx,
  std::vector<Tensor>* out_tensors,
  bool* end_of_sequence) override {
  