anchor.diff:        timer.cancel();
         // foo is called again to make sure we can still run it even after
         // its code has been detached.
  -      foo(2);
  +      var ret = foo(2);
  +      print("foo=$ret");
       }
     });
   }
  
positive.code: 
  
  doTest() {
   var i = 0;
    foo(1);  // Initial call to compile.
    // Time passes, GC runs, foo's code is dropped.
    var ms = const Duration(milliseconds: 100);
    var t = new Timer.periodic(ms, (timer) {
  
negative.code:     // Run the test and capture stdout.
      var pr = Process.runSync(Platform.executable,
          ["--collect-code",
           "--code-collection-interval-in-us=0",
           "--old_gen_growth_rate=10",
           "--log-code-drop",
           "--optimization-counter-threshold=-1",
  