Improve terminology around "after typeck"

compiler/rustc_trait_selection/src/traits/project.rs

@@ -392,7 +392,7 @@ impl<'a, 'b, 'tcx> TypeFolder<'tcx> for AssocTypeNormalizer<'a, 'b, 'tcx> {
             // severe performance implications for large opaque types with
             // late-bound regions. See `issue-88862` benchmark.
             ty::Opaque(def_id, substs) if !substs.has_escaping_bound_vars() => {
-                // Only normalize `impl Trait` after type-checking, usually in codegen.
+                // Only normalize `impl Trait` outside of type inference, usually in codegen.
                 match self.param_env.reveal() {
                     Reveal::UserFacing => ty.super_fold_with(self),