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

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

Index: sdk/lib/_internal/pub_generated/test/serve/serves_file_with_space_test.dart
diff --git a/sdk/lib/_internal/pub/test/serve/serves_file_with_space_test.dart b/sdk/lib/_internal/pub_generated/test/serve/serves_file_with_space_test.dart
similarity index 67%
copy from sdk/lib/_internal/pub/test/serve/serves_file_with_space_test.dart
copy to sdk/lib/_internal/pub_generated/test/serve/serves_file_with_space_test.dart
index eead8082839c9d4283c884473baf40648f6c38a7..d2421cff64a58b98bff9d95d24268fd347afac1e 100644
--- a/sdk/lib/_internal/pub/test/serve/serves_file_with_space_test.dart
+++ b/sdk/lib/_internal/pub_generated/test/serve/serves_file_with_space_test.dart
@@ -11,15 +11,15 @@ import 'utils.dart';
 main() {
   initConfig();
   integration("serves a filename with a space", () {
-    d.dir(appPath, [
-      d.appPubspec(),
-      d.dir("web", [
-        d.file("foo bar.txt", "outer contents"),
-        d.dir("sub dir", [
-          d.file("inner.txt", "inner contents"),
-        ])
-      ])
-    ]).create();
+    d.dir(
+        appPath,
+        [
+            d.appPubspec(),
+            d.dir(
+                "web",
+                [
+                    d.file("foo bar.txt", "outer contents"),
+                    d.dir("sub dir", [d.file("inner.txt", "inner contents"),])])]).create();
 
     pubServe();
     requestShouldSucceed("foo%20bar.txt", "outer contents");