code: public CharsTrie saveState(State state) /*const*/ {
          state.chars=chars_;
          state.root=root_;
          state.pos=pos_;
          state.remainingMatchLength=remainingMatchLength_;
          return this;
      }
docs: Saves the state of this trie.
  @param state The State object to hold the trie's state.
  @return this
  @see #resetToState