BlittableStructPtrMarshaller not implemented

[sergiy-k]

Repro:

        try
        {
            string path = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);
            Console.WriteLine("Pass: folder path '{0}'", path);
        }
        catch (Exception e)
        {
            Console.WriteLine("Failure: {0}", e.ToString());
        }

It fails with the following exception:

System.Exception: Method '[System.Runtime.Extensions]Shell32.SHGetKnownFolderPath' requires non-trivial marshalling that is not yet supported by this compiler.