message: [accumulator] fix merge error
diff: @@ -483,6 +483,23 @@ impl AccumulatorCache {
  precondition!(num_new_leaves * 2 <= usize::max_value() - root_level as usize);
  num_new_leaves * 2 + root_level as usize
  }
  +
  + fn get_vec_hash(node_vec: Vec<AccumulatorNode>) -> Result<Vec<HashValue>> {
  + let mut hash_vec = vec![];
  + for node in node_vec {
  + hash_vec.push(node.hash());
  + }
  + Ok(hash_vec)
  + }
  +
  + pub fn get_info(&self) -> AccumulatorInfo {
  + AccumulatorInfo::new(
  + self.frozen_subtree_roots.borrow().clone(),
  + self.num_leaves,
  + self.num_nodes,
  + self.root_hash,
  + )
  + }
  }
  impl MerkleAccumulator {
  