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

tests/language/no_such_method_dispatcher_test.dart

 // 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 --no-use-osr
+// VMOptions=--optimization-counter-threshold=10 --no-use-osr --no-background-compilation
 
 import "package:expect/expect.dart";
 
 // Test that noSuchMethod dispatching and auto-closurization work correctly.
 
 class A {
   noSuchMethod(m) {
     return 123;
   }
   bar(x) => x + 1;
@@ skipping 38 matching lines @@
   }
 
   // Test named and positional arguments.
   var c = new C(1, 2, [100], {"n1":101, "n2":102});
   for (var i = 0; i < 20; ++i) {
     Expect.equals(123, c.bar(100, n1:101, n2:102));
     Expect.equals(123, c.bar(100, n2:102, n1:101));
   }
 }