Function TestExists

tests/gtest/gtest.h:7032–7034

  }

  bool TestExists(const std::string& test_name) const {
    return registered_tests_.count(test_name) > 0;
  }

  const CodeLocation& GetCodeLocation(const std::string& test_name) const {
    RegisteredTestsMap::const_iterator it = registered_tests_.find(test_name);