Method MatchAndExplain

tests/gtest/gtest.h:9450–9453

   public:
    explicit Impl(const Rhs& rhs) : rhs_(rhs) {}
    bool MatchAndExplain(Lhs lhs,
                         MatchResultListener* /* listener */) const override {
      return Op()(lhs, Unwrap(rhs_));
    }
    void DescribeTo(::std::ostream* os) const override {
      *os << D::Desc() << " ";
      UniversalPrint(Unwrap(rhs_), os);