// Increments the death test count, returning the new count.
  int increment_death_test_count() { return ++death_test_count_; }

  // Clears the test part results.
  void ClearTestPartResults();

  // Clears the object.
  void Clear();

  // Protects mutable state of the property vector and of owned
  // properties, whose values may be updated.
  internal::Mutex test_properties_mutex_;

  // Increments the death test count, returning the new count.
  int increment_death_test_count() { return ++death_test_count_; }

  // Clears the test part results.
  void ClearTestPartResults();

  // Clears the object.
  void Clear();

  // Protects mutable state of the property vector and of owned
  // properties, whose values may be updated.
  internal::Mutex test_properties_mutex_;