lingering step 2 of the test rename overhaul: make await tests also a directory

frog/tests/await/while_normalization_test.dart

Index: frog/tests/await/while_normalization_test.dart
diff --git a/frog/tests/await/while_normalization_test.dart b/frog/tests/await/while_normalization_test.dart
index 2d3e2a3a4f760df9a07c66915b17ba761ae113d9..3d1648af61e5595d3b8ddb4f7ac423d674811152 100644
--- a/frog/tests/await/while_normalization_test.dart
+++ b/frog/tests/await/while_normalization_test.dart
@@ -2,6 +2,9 @@
 // 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.
 
+// Pass VM options to run test through the awaitc compiler:
+// VMOptions=frog/await/awaitc.dart
+
 // Await within the test of a while loop.
 
 #import("await_test_helper.dart");