ignore the root returned in Commit function for simplicity

Author: ucwong

core/state/state_object.go

@@ -454,9 +454,9 @@ func (s *stateObject) commit() error {
 	if s.dbErr != nil {
 		return s.dbErr
 	}
-	root, err := s.trie.Commit(nil)
+	_, err := s.trie.Commit(nil)
 	if err == nil {
-		s.data.Root = root
+		//s.data.Root = root
 		// Update original account data after commit
 		s.origin = s.data.Copy()
 	}

core/state/statedb.go

@@ -1048,7 +1048,7 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 		return common.Hash{}, fmt.Errorf("commit aborted due to earlier error: %v", s.dbErr)
 	}
 	// Finalize any pending changes and merge everything into the tries
-	s.IntermediateRoot(deleteEmptyObjects)
+	root := s.IntermediateRoot(deleteEmptyObjects)
 
 	start := time.Now()
 	// Commit objects to the trie, measuring the elapsed time
@@ -1101,7 +1101,7 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 	// The onleaf func is called _serially_, so we can reuse the same account
 	// for unmarshalling every time.
 	var account types.StateAccount
-	root, err := s.trie.Commit(func(_ [][]byte, _ []byte, leaf []byte, parent common.Hash) error {
+	_, err := s.trie.Commit(func(_ [][]byte, _ []byte, leaf []byte, parent common.Hash) error {
 		if err := rlp.DecodeBytes(leaf, &account); err != nil {
 			return nil
 		}