Remove hints in build of try

site/try/src/leap.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.
 
 library trydart.main;
 
 import 'dart:html' show
     HttpRequest,
     LinkElement,
     querySelector,
     window;
 
 import 'dart:isolate' show
     Isolate,
     ReceivePort,
     SendPort;
 
 import 'compilation.dart' show
-    compilerIsolate,
     compilerPort,
     currentSource;
 
 import 'samples.dart' show
     EXAMPLE_HELLO;
 
 import 'ui.dart' show
     buildUI,
     interaction,
     observer;
@@ skipping 47 matching lines @@
           interaction.onMutation([], observer);
           break;
         default:
           // TODO(ahe): Close [port]?
           print('Unexpected message received: $message');
           break;
       }
     });
   });
 }