[esnext] Fix various callsites to use is_resumable, not is_generator

test/mjsunit/harmony/debug-async-break-on-stack.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: --expose-debug-as debug
 // Flags: --harmony-async-await --allow-natives-syntax
 
+var Debug = debug.Debug;
+
 function assertEqualsAsync(expected, run, msg) {
   var actual;
   var hadValue = false;
   var hadError = false;
   var promise = run();
 
   if (typeof promise !== "object" || typeof promise.then !== "function") {
     throw new MjsUnitAssertionError(
         "Expected " + run.toString() +
-        " to return a Promise, but it returned " + PrettyPrint(promise));
+        " to return a Promise, but it returned " + promise);
   }
 
   promise.then(function(value) { hadValue = true; actual = value; },
                function(error) { hadError = true; actual = error; });
 
   assertFalse(hadValue || hadError);
 
   %RunMicrotasks();
 
   if (hadError) throw actual;
 
   assertTrue(
       hadValue, "Expected '" + run.toString() + "' to produce a value");
 
   assertEquals(expected, actual, msg);
-};
+}
 
-class BaseClass {
-  constructor(x) {
-    this.name_ = x;
+var break_count = 0;
+var exception = null;
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Break) return;
+  try {
+    break_count++;
+    var line = exec_state.frame(0).sourceLineText();
+    print(line);
+    assertTrue(line.indexOf(`B${break_count}`) > 0);
+  } catch (e) {
+    exception = e;
   }
-  get name() { return this.name_; }
-};
-
-class DeferredSuperCall extends BaseClass {
-  constructor(x) {
-    return async() => super(x);
-  }
-};
-
-assertEqualsAsync(
-  "LexicalSuperCall",
-  () => new DeferredSuperCall("LexicalSuperCall")().then(x => x.name));
+}
 
 
-class DeferredSuperProperty extends BaseClass {
-  deferredName() { return async() => super.name; }
-};
+async function g() {
+  setbreaks();
+  throw 1;  // B1
+}
 
-assertEqualsAsync(
-  "LexicalSuperProperty",
-  () => new DeferredSuperProperty("LexicalSuperProperty").deferredName()());
+async function f() {
+  try {
+    await g();
+  } catch (e) {}
+  return 2;  // B2
+}
+
+function setbreaks() {
+  Debug.setListener(listener);
+  Debug.setBreakPoint(g, 2);
+  Debug.setBreakPoint(f, 4);
+}
+
+f();
+
+%RunMicrotasks();
+
+assertEqualsAsync(2, async () => break_count);
+assertEqualsAsync(null, async () => exception);
+
+Debug.setListener(null);