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

sdk/lib/_internal/pub_generated/test/build/outputs_results_to_json_test.dart

Index: sdk/lib/_internal/pub_generated/test/build/outputs_results_to_json_test.dart
diff --git a/sdk/lib/_internal/pub_generated/test/build/outputs_results_to_json_test.dart b/sdk/lib/_internal/pub_generated/test/build/outputs_results_to_json_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..8eff17dad4ca5f549fac6c5ed8be8b813f29ccc2
--- /dev/null
+++ b/sdk/lib/_internal/pub_generated/test/build/outputs_results_to_json_test.dart
@@ -0,0 +1,75 @@
+// 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.
+
+import 'package:scheduled_test/scheduled_test.dart';
+
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+
+main() {
+  initConfig();
+
+  integration("outputs results to JSON in a successful build", () {
+    // Dart2js can take a long time to compile dart code, so we increase the
+    // timeout to cope with that.
+    currentSchedule.timeout *= 3;
+
+    d.dir(
+        appPath,
+        [
+            d.appPubspec(),
+            d.dir(
+                'web',
+                [d.file('main.dart', 'void main() => print("hello");')])]).create();
+
+    schedulePub(args: ["build", "--format", "json"], outputJson: {
+      'buildResult': 'success',
+      'outputDirectory': 'build',
+      'numFiles': 1,
+      'log': [{
+          'level': 'Info',
+          'transformer': {
+            'name': 'Dart2JS',
+            'primaryInput': {
+              'package': 'myapp',
+              'path': 'web/main.dart'
+            }
+          },
+          'assetId': {
+            'package': 'myapp',
+            'path': 'web/main.dart'
+          },
+          'message': 'Compiling myapp|web/main.dart...'
+        }, {
+          'level': 'Info',
+          'transformer': {
+            'name': 'Dart2JS',
+            'primaryInput': {
+              'package': 'myapp',
+              'path': 'web/main.dart'
+            }
+          },
+          'assetId': {
+            'package': 'myapp',
+            'path': 'web/main.dart'
+          },
+          'message': contains(r'to compile myapp|web/main.dart.')
+        }, {
+          'level': 'Fine',
+          'transformer': {
+            'name': 'Dart2JS',
+            'primaryInput': {
+              'package': 'myapp',
+              'path': 'web/main.dart'
+            }
+          },
+          'assetId': {
+            'package': 'myapp',
+            'path': 'web/main.dart'
+          },
+          'message': contains(r'Took')
+        }]
+    });
+  });
+}