message: Fix asan/msan failures.
diff: @@ -2463,6 +2463,9 @@ EstimateWindowedEinsumIterationsForNonContractingPartitioning(
  output_other_non_contracting_partitions, other_sharding,
  output_sharding, matching_non_contracting_dims,
  other_non_contracting_dims, dims_mapping.contracting_dims);
  + if (!other_grouped) {
  + return absl::nullopt;
  + }
  absl::optional<HloSharding> output_sharding_transposed_to_match_matching =
  hlo_sharding_util::TransposeShardingWithCollapsedDims(
  output_grouped.sharding, output_to_matching_indices,
  