Query: Chained GroupBy with aggregate throws

[smitpatel]

    var query = db.Blogs
        .GroupBy(b => new { b.Id, b.Author })
        .GroupBy(b => b.Key.Author)
        .Select(g => g.Count())
        .ToList();

We assume this is aggregate and try to translate it but it fails since it is not.

[ajcvickers]

Duplicate of #11904