Untested hacks to swarm to avoid warnings.

samples-dev/swarm/swarm_ui_lib/touch/TouchUtil.dart

 // Copyright (c) 2011, 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.
 
 part of touch;
 
 /**
  * Wraps a callback with translations of mouse events to touch events. Use
  * this function to invoke your callback that expects touch events after
  * touch events are created from the actual mouse events.
@@ skipping 253 matching lines @@
   bool get metaKey => wrapped.metaKey;
 
   bool get shiftKey => wrapped.shiftKey;
 
   DataTransfer get clipboardData { throw new UnimplementedError(); }
   Point get layer { throw new UnimplementedError(); }
   Element get matchingTarget { throw new UnimplementedError(); }
   Point get page { throw new UnimplementedError(); }
   List get path { throw new UnimplementedError(); }
   Point get screen { throw new UnimplementedError(); }
+  /*InputDevice*/ get sourceDevice { throw new UnimplementedError(); }
 }