Method ComparisonBase

tests/gtest/gtest.h:9434–9434

class ComparisonBase {
 public:
  explicit ComparisonBase(const Rhs& rhs) : rhs_(rhs) {}
  template <typename Lhs>
  operator Matcher<Lhs>() const {
    return Matcher<Lhs>(new Impl<const Lhs&>(rhs_));