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

sdk/lib/_internal/pub_generated/test/serve/invalid_urls_test.dart

Index: sdk/lib/_internal/pub_generated/test/serve/invalid_urls_test.dart
diff --git a/sdk/lib/_internal/pub/test/serve/invalid_urls_test.dart b/sdk/lib/_internal/pub_generated/test/serve/invalid_urls_test.dart
similarity index 69%
copy from sdk/lib/_internal/pub/test/serve/invalid_urls_test.dart
copy to sdk/lib/_internal/pub_generated/test/serve/invalid_urls_test.dart
index 29c73a1660083fe3ef1aa5829afa4e81aeeb8c75..ece122e71b826d184bce78dc539449a955a7631d 100644
--- a/sdk/lib/_internal/pub/test/serve/invalid_urls_test.dart
+++ b/sdk/lib/_internal/pub_generated/test/serve/invalid_urls_test.dart
@@ -11,23 +11,18 @@ import 'utils.dart';
 main() {
   initConfig();
   integration("responds with a 404 on incomplete special URLs", () {
-    d.dir("foo", [
-      d.libPubspec("foo", "0.0.1")
-    ]).create();
+    d.dir("foo", [d.libPubspec("foo", "0.0.1")]).create();
 
-    d.dir(appPath, [
-      d.appPubspec({
-        "foo": {"path": "../foo"}
+    d.dir(appPath, [d.appPubspec({
+        "foo": {
+          "path": "../foo"
+        }
       }),
-      d.dir("lib", [
-        // Make a file that maps to the special "packages" directory to ensure
+          d.dir(
+              "lib",
+              [// Make a file that maps to the special "packages" directory to ensure
         // it is *not* found.
-        d.file("packages")
-      ]),
-      d.dir("web", [
-        d.file("packages")
-      ])
-    ]).create();
+        d.file("packages")]), d.dir("web", [d.file("packages")])]).create();
 
     pubGet();
     pubServe();