message: Fix the assumption of static weights in MergeDensify
diff: @@ -46,10 +46,11 @@ class MergeDensify : public NodeTransformation {
  if (inputs.size() != 2) return {TransformStatus::SKIPPED, ""};
  const Node* dequantize_or_densify = graph->FindProducer(inputs[1]->id);
  - if (dequantize_or_densify->operation.type !=
  + if (!dequantize_or_densify ||
  + (dequantize_or_densify->operation.type !=
  ToString(OperationType::DENSIFY) &&
  dequantize_or_densify->operation.type !=
  - ToString(OperationType::QUANTIZE_AND_DEQUANTIZE)) {
  + ToString(OperationType::QUANTIZE_AND_DEQUANTIZE))) {
  return {TransformStatus::SKIPPED, ""};
  }
  const Node* dequantize_node;
  