Remove unnecessary generator-check, which also fixes the issue within async functions

Author: oli-obk

compiler/rustc_mir_transform/src/reveal_all.rs

@@ -9,11 +9,6 @@ pub struct RevealAll;
 
 impl<'tcx> MirPass<'tcx> for RevealAll {
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
-        // Do not apply this transformation to generators.
-        if body.generator.is_some() {
-            return;
-        }
-
         let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
         RevealAllVisitor { tcx, param_env }.visit_body_preserves_cfg(body);
     }

tests/ui/type-alias-impl-trait/destructure_tait-ice-113594.rs

@@ -1,4 +1,5 @@
 // build-pass
+// edition: 2021
 
 #![feature(type_alias_impl_trait)]
 
@@ -9,7 +10,7 @@ pub struct Foo {
 
 pub type Tait = impl Sized;
 
-pub fn ice_cold(beverage: Tait) {
+pub async fn ice_cold(beverage: Tait) {
     // Must destructure at least one field of `Foo`
     let Foo { field } = beverage;
     _ = field;