windowscodecs: Implement GetThumbnail in the ICO frame decoder.

[Hans Leidekker]

On Wed, 2013-01-30 at 18:02 +0800, Dmitry Timoshkov wrote:
> diff --git a/dlls/windowscodecs/icoformat.c b/dlls/windowscodecs/icoformat.c
> index 7aec245..da5a733 100644
> --- a/dlls/windowscodecs/icoformat.c
> +++ b/dlls/windowscodecs/icoformat.c
> @@ -200,8 +200,12 @@ static HRESULT WINAPI IcoFrameDecode_GetColorContexts(IWICBitmapFrameDecode *ifa
>  static HRESULT WINAPI IcoFrameDecode_GetThumbnail(IWICBitmapFrameDecode *iface,
>      IWICBitmapSource **ppIThumbnail)
>  {
> -    FIXME("(%p,%p)\n", iface, ppIThumbnail);
> -    return E_NOTIMPL;
> +    TRACE("(%p,%p)\n", iface, ppIThumbnail);
> +
> +    if (!ppIThumbnail) return E_INVALIDARG;
> +
> +    *ppIThumbnail = NULL;
> +    return WINCODEC_ERR_CODECNOTHUMBNAIL;
>  }

The test added by 6395af1ae7b0cc5f2f1f82796502e2a605bc5a6b says otherwise, GetThumbnail
is supported for ICO frames.