Revert "Use native async/await support in pub."

sdk/lib/_internal/pub_generated/test/snapshot/recompiles_if_the_sdk_is_out_of_date_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library pub_tests;
 
 import 'package:path/path.dart' as p;
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:scheduled_test/scheduled_stream.dart';
 
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 
 main() {
   initConfig();
-  integration("creates a snapshot for an immediate dependency's executables",
+  integration(
+      "creates a snapshot for an immediate dependency's executables",
       () {
     servePackages((builder) {
-      builder.serve("foo", "5.6.7", contents: [
-        d.dir("bin", [d.file("hello.dart", "void main() => print('hello!');")])
-      ]);
+      builder.serve(
+          "foo",
+          "5.6.7",
+          contents: [
+              d.dir("bin", [d.file("hello.dart", "void main() => print('hello!');")])]);
     });
 
-    d.appDir({"foo": "5.6.7"}).create();
+    d.appDir({
+      "foo": "5.6.7"
+    }).create();
 
     pubGet(output: contains("Precompiled foo:hello."));
 
-    d.dir(p.join(appPath, '.pub', 'bin'), [
-      d.dir('foo', [d.outOfDateSnapshot('hello.dart.snapshot')])
-    ]).create();
+    d.dir(
+        p.join(appPath, '.pub', 'bin'),
+        [d.dir('foo', [d.outOfDateSnapshot('hello.dart.snapshot')])]).create();
 
     var process = pubRun(args: ['foo:hello']);
 
     // In the real world this would just print "hello!", but since we collect
     // all output we see the precompilation messages as well.
     process.stdout.expect("Precompiling executables...");
     process.stdout.expect(consumeThrough("hello!"));
     process.shouldExit();
 
-    d.dir(p.join(appPath, '.pub', 'bin'), [
-      d.file('sdk-version', '0.1.2+3'),
-      d.dir('foo', [d.matcherFile('hello.dart.snapshot', contains('hello!'))])
-    ]).create();
+    d.dir(
+        p.join(appPath, '.pub', 'bin'),
+        [
+            d.file('sdk-version', '0.1.2+3'),
+            d.dir(
+                'foo',
+                [d.matcherFile('hello.dart.snapshot', contains('hello!'))])]).create();
   });
 }