message: [XLA] Don't pass span by const reference
  Span is cheap and trivially copyable.
diff: @@ -2790,7 +2790,7 @@ class HloEvaluatorTypedVisitor : public DfsHloVisitorWithDefault {
  // bound, call `f` with the base index.
  static void IterateThroughWindow(
  const Shape& window_shape, const Window& window, const Shape& base_shape,
  - const absl::Span<const int64>& window_count_index,
  + const absl::Span<const int64> window_count_index,
  const std::function<void(const std::vector<int64>&)>& f) {
  const int64 rank = base_shape.rank();
  DimensionVector window_index(rank);
  