code: func (self *stateObject) CommitTrie(db Database) error {
  	self.updateTrie(db)
  	if self.dbErr != nil {
  		return self.dbErr
  	}
  	// Track the amount of time wasted on committing the storge trie
  	if metrics.EnabledExpensive {
  		defer func(start time.Time) { self.db.StorageCommits += time.Since(start) }(time.Now())
  	}
  	root, err := self.trie.Commit(nil)
  	if err == nil {
  		self.data.Root = root
  	}
  	return err
  }
docs: // CommitTrie the storage trie of the object to db.
  // This updates the trie root.