message: Fix issue when Table iterator reached the end
diff: @@ -2281,7 +2281,7 @@ ClusterTree::ConstIterator& Table::ConstIterator::operator+=(ptrdiff_t adj)
  if (k != m_key) {
  // Objects was deleted. k points to the next object
  m_key = k;
  - m_position = m_tree.get_ndx(m_key);
  + m_position = m_key ? m_tree.get_ndx(m_key) : m_tree.size();
  n--;
  }
  }
  