Remove two comments that shouldn't be there.

Author: nnethercote

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -881,7 +881,6 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                         &item.vis,
                         errors::VisibilityNotPermittedNote::TraitImpl,
                     );
-                    // njn: use Dummy here
                     if let TyKind::Err(_) = self_ty.kind {
                         this.dcx().emit_err(errors::ObsoleteAuto { span: item.span });
                     }

compiler/rustc_errors/src/lib.rs

@@ -1276,7 +1276,6 @@ impl DiagCtxtInner {
     fn emit_stashed_diagnostics(&mut self) {
         let has_errors = !self.err_guars.is_empty();
         for (_, diag) in std::mem::take(&mut self.stashed_diagnostics).into_iter() {
-            // Decrement the count tracking the stash; emitting will increment it.
             if diag.is_error() {
                 if diag.is_lint.is_none() {
                     self.stashed_err_count -= 1;