associated types with generic bounds not in where clause won't compile

[bsh98]

For example, the following trait compiles

#[trait_variant::make(TestTrait: Send)]
pub trait LocalTestTrait{
    type B<T>: FromIterator<T> where T: Display;
    // --snip--
}

but this one does not compile

#[trait_variant::make(TestTrait: Send)]
pub trait LocalTestTrait{
    type B<T: Display>: FromIterator<T>;
    // --snip--
}

even though they are equivalent.