Remove anon struct and union types

compiler/rustc_ast/src/ast.rs

@@ -2167,10 +2167,6 @@ pub enum TyKind {
     Never,
     /// A tuple (`(A, B, C, D,...)`).
     Tup(ThinVec<P<Ty>>),
-    /// An anonymous struct type i.e. `struct { foo: Type }`.
-    AnonStruct(NodeId, ThinVec<FieldDef>),
-    /// An anonymous union type i.e. `union { bar: Type }`.
-    AnonUnion(NodeId, ThinVec<FieldDef>),
     /// A path (`module::module::...::Type`), optionally
     /// "qualified", e.g., `<Vec<T> as SomeTrait>::SomeType`.
     ///
@@ -2227,10 +2223,6 @@ impl TyKind {
             None
         }
     }
-
-    pub fn is_anon_adt(&self) -> bool {
-        matches!(self, TyKind::AnonStruct(..) | TyKind::AnonUnion(..))
-    }
 }
 
 /// Syntax used to declare a trait object.