Prune commentary and stale Rust port notes

core/src/widget/like.rs

@@ -43,7 +43,6 @@ impl<Rsc, const LEN: usize> WidgetArrLike<Rsc, LEN, ArrTag> for WidgetArr<LEN> {
     }
 }
 
-// variadic generics please save us
 macro_rules! impl_widget_arr {
     ($n:expr;$($W:ident)*) => {
         impl_widget_arr!($n;$($W)*;$(${concat($W,Tag)})*);