[debugger] Stepping and break-related functions in wrapper

test/debugger/debug/harmony/debug-async-function-async-task-event.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-async-await --expose-debug-as debug --allow-natives-syntax
+// Flags: --harmony-async-await
 
 // The test observes the callbacks that async/await makes to the inspector
 // to make accurate stack traces. The pattern is based on saving a stack once
 // with enqueueRecurring and restoring it multiple times.
 
 // Additionally, the limited number of events is an indirect indication that
 // we are not doing extra Promise processing that could be associated with memory
 // leaks (v8:5380). In particular, no stacks are saved and restored for extra
 // Promise handling on throwaway Promises.
 
@@ skipping 72 matching lines @@
 confused();
 
 Promise.resolve().then(() => {
   Debug.setListener(listener);
   Debug.setBreakOnUncaughtException();
   resolve();
 });
 
 %RunMicrotasks();
 assertNull(exception);