Update the dartdoc for the interactive unittest config to note debugger compatibility issues.

pkg/unittest/lib/interactive_html_config.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.
 
 /**
  * This configuration can be used to rerun selected tests, as well
  * as see diagnostic output from tests. It runs each test in its own
  * IFrame, so the configuration consists of two parts - a 'parent'
  * config that manages all the tests, and a 'child' config for the
  * IFrame that runs the individual tests.
+ * 
+ * Note: this unit test configuration will not work with the debugger (the tests
+ * are executed in a separate IFrame).
  */
 library unittest_interactive_html_config;
 
 // TODO(gram) - add options for: remove IFrame on done/keep
 // IFrame for failed tests/keep IFrame for all tests.
 
 import 'dart:html';
 import 'dart:async';
 import 'dart:math';
 import 'unittest.dart';
@@ skipping 434 matching lines @@
     document.body.nodes.add(new Element.html(
         "<div id='busy' style='display:none'><img src='googleballs.gif'>"
         "</img></div>"));
   }
   if (document.query('#child') == null) {
     document.body.nodes.add(new Element.html("<div id='child'></div>"));
   }
 }
 
 /**
- * Allocate a Configuration. We allocate either a parent or
- * child, depending on whether the URL has a search part.
+ * Allocate a Configuration. We allocate either a parent or child, depending on
+ * whether the URL has a search part.
+ * 
+ * Note: this unit test configuration will not work with the debugger (the tests
+ * are executed in a separate IFrame).
  */
 void useInteractiveHtmlConfiguration() {
   if (window.location.search == '') { // This is the parent.
     _prepareDom();
     unittestConfiguration = _singletonParent;
   } else {
     unittestConfiguration = _singletonChild;
   }
 }
 
@@ skipping 192 matching lines @@
 display: block;
 list-style-type: disc;
 -webkit-margin-before: 1em;
 -webkit-margin-after: 1em;
 -webkit-margin-start: 0px;
 -webkit-margin-end: 0px;
 -webkit-padding-start: 40px;
 }
 
   """;