Don't implicitly run "pub get".

test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart

Index: test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart
diff --git a/test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart b/test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart
index 92645035ceaf4f19f368ba28f1bf953201f10677..280f0f37b151daaefb288073c6e0b28395b7c822 100644
--- a/test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart
+++ b/test/serve/gets_first_if_transitive_dependency_is_not_installed_test.dart
@@ -33,7 +33,8 @@ main() {
     // Delete the system cache so bar isn't installed any more.
     schedule(() => deleteEntry(path.join(sandboxDir, cachePath)));
 
-    pubServe(shouldGetFirst: true);
+    pubGet();
+    pubServe();
     requestShouldSucceed("packages/bar/bar.dart", 'main() => "bar 1.2.3";');
     endPubServe();
   });