anchor.diff:  /// used, through a call to `WindowsDeleteString()`.
   /// {@category winrt}
   Pointer<IntPtr> convertToHString(String string) {
  -  final hString = allocate<IntPtr>();
  -
  +  final hString = calloc<IntPtr>();
     // Create a HSTRING representing the object
     final hr = WindowsCreateString(Utf16.toUtf16(string), string.length, hString);
     if (FAILED(hr)) {
  
positive.code: /// {@category winrt}
  Pointer<IntPtr> CreateObject(String className, String iid) {
    final hstrClass = allocate<IntPtr>();
  
    // Create a HSTRING representing the object
    var hr = WindowsCreateString(
        Utf16.toUtf16(className), className.length, hstrClass);
    if (FAILED(hr)) {
      throw WindowsException(hr);
    }
    // Activates the specified Windows Runtime class. This returns the WinRT
    // IInspectable interface, which is a subclass of IUnknown.
    final inspectablePtr = allocate<Pointer>();
    hr = RoActivateInstance(hstrClass.value, inspectablePtr);
    if (FAILED(hr)) {
      throw WindowsException(hr);
    }
  
    // Create an IID for the interface required
    final riidCalendar = calloc<GUID>();
    hr = IIDFromString(TEXT(iid), riidCalendar);
    if (FAILED(hr)) {
      throw WindowsException(hr);
    }
  
    // Now use IInspectable to navigate to the relevant interface
    final inspectable = IInspectable(inspectablePtr.cast());
    final classPtr = allocate<IntPtr>();
    hr = inspectable.QueryInterface(riidCalendar, classPtr);
    if (FAILED(hr)) {
      throw WindowsException(hr);
    }
  
    // Return a pointer to the relevant class
    return classPtr;
  }
  
negative.code: /// {@category winrt}
  String convertFromHString(Pointer<IntPtr> hstring) {
    final stringLength = allocate<Uint32>();
  
    try {
      final stringPtr = WindowsGetStringRawBuffer(hstring.value, stringLength);
      final dartString = stringPtr.unpackString(stringLength.value);
  
      return dartString;
    } finally {
      free(stringLength);
    }
  }
  
  /// Takes a Dart String and converts it to an `HSTRING` (a WinRT String),
  