Add --no-background-compilation to tests that expect to run code in optimized form

tests/lib/typed_data/int32x4_shuffle_test.dart

Index: tests/lib/typed_data/int32x4_shuffle_test.dart
diff --git a/tests/lib/typed_data/int32x4_shuffle_test.dart b/tests/lib/typed_data/int32x4_shuffle_test.dart
index d2b4bc6e37ec3de983f89b8179e2049b424a588b..79d81c7093c967759db8ee68ca6c995ee4c1826e 100644
--- a/tests/lib/typed_data/int32x4_shuffle_test.dart
+++ b/tests/lib/typed_data/int32x4_shuffle_test.dart
@@ -1,7 +1,7 @@
 // Copyright (c) 2013, 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.
-// VMOptions=--optimization-counter-threshold=10
+// VMOptions=--optimization-counter-threshold=10 --no-background-compilation
 
 // Library tag to be able to run in html test framework.
 library uint32x4_shuffle_test;