Don't quit debugger when the program terminates, only after `quit`.

tests/debugger/break_in_anonymous_function_test.dart

 // Copyright (c) 2016, the Dartino 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.md file.
 
 // Test that we can set a breakpoint in the body of an anonymous function.
 
-// DartinoDebuggerCommands=bf tests/debugger/break_in_anonymous_function_test.dart 12,bf tests/debugger/break_in_anonymous_function_test.dart 17,bf tests/debugger/break_in_anonymous_function_test.dart 19,r,c,c,c
+// DartinoDebuggerCommands=bf tests/debugger/break_in_anonymous_function_test.dart 12,bf tests/debugger/break_in_anonymous_function_test.dart 17,bf tests/debugger/break_in_anonymous_function_test.dart 19,r,c,c,c,q
 
 import 'package:expect/expect.dart';
 
 var foo = () {
   return 1 + 2 + 3;
 };
 
 main() {
   var local = (i) {
     Expect.equals(3, i);
     return (j) {
       Expect.equals(5, j);
       return 42;
     }(i + 2);
   };
   Expect.equals(6, foo());
   Expect.equals(42, local(3));
 }