Remove --harmony-async-await runtime flag

test/mjsunit/harmony/async-await-species.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 --allow-natives-syntax
-
-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));
-  }
-
-  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);
-};
-
-// Rename a function so that it can help omit things from stack trace.
-function test(fn) {
-  return Object.defineProperty(fn, "name", {
-      enumerable: false,
-      configurable: true,
-      value: "@" + fn.name,
-      writable: false
-    });
-}
-
-function getStack(error) {
-  var stack = error.stack.split('\n').
-    filter(function(line) {
-        return /^\s*at @?[a-zA-Z0-9_]/.test(line);
-    }).
-    map(line => line.replace(/^\s*at (@?[a-zA-Z0-9_\.\[\]]+)(.*)/, "$1"));
-
-  // remove `Promise.then()` invocation by assertEqualsAsync()
-  if (stack[2] === "assertEqualsAsync") return [];
-
-  return stack.reverse();
-}
-
-var log = [];
-class FakePromise extends Promise {
-  constructor(executor) {
-    var stack = getStack(new Error("Getting Callstack"));
-    if (stack.length) {
-      var first = -1;
-      for (var i = 0; i < stack.length; ++i) {
-        if (stack[i][0] === '@') {
-          first = i;
-          break;
-        }
-      }
-      while (first > 0) stack.shift(), --first;
-      if (stack.length) {
-        log.push("@@Species: [" + stack.join(" > ") + "]");
-      }
-    }
-    return new Promise(executor);
-  }
-};
-
-Object.defineProperty(Promise, Symbol.species, {
-  value: FakePromise,
-  configurable: true,
-  enumerable: false,
-  writable: false
-});
-
-// Internal `AsyncFunctionAwait` only --- no @@species invocations.
-async function asyncFn() { return await "foo"; }
-assertEqualsAsync("foo", test(function testInternalOnly() { return asyncFn(); },
-                  "should not call Promise[@@Species]"));
-assertEquals([], log);
-
-log.length = 0;
-assertEqualsAsync(
-    "foo",
-    test(function testThenOnReturnedPromise() {
-      return asyncFn().then(x => (log.push("Then: " + x), x));
-    }),
-    "should call Promise[@@Species] after non-internal Then");
-assertEquals([
-  "@@Species: [@testThenOnReturnedPromise > Promise.then > FakePromise]",
-  "Then: foo"
-], log);