message: Fix shape matching check
diff: @@ -866,7 +866,7 @@ class HoistCommonFactorOutOfAggregation : public ArithmeticOptimizerStage {
  *shapes_match = true;
  unique_factors->reserve(node->input_size());
  - for (int i = 0; i < node->input_size() && shapes_match; ++i) {
  + for (int i = 0; i < node->input_size() && *shapes_match; ++i) {
  const string& input = node->input(i);
  if (IsControlInput(input)) {
  break;
  