Adding isNotEmpty property to collection and string.

sdk/lib/io/http_session.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.
 
 part of dart.io;
 
 const String _DART_SESSION_ID = "DARTSESSID";
 
 // A _HttpSession is a node in a double-linked list, with _next and _prev being
 // the previous and next pointers.
@@ skipping 42 matching lines @@
   operator [](key) => _data[key];
   void operator []=(key, value) { _data[key] = value; }
   putIfAbsent(key, ifAbsent) => _data.putIfAbsent(key, ifAbsent);
   remove(key) => _data.remove(key);
   void clear() => _data.clear();
   void forEach(void f(key, value)) => _data.forEach(f);
   Iterable get keys => _data.keys;
   Iterable get values => _data.values;
   int get length => _data.length;
   bool get isEmpty => _data.isEmpty;
+  bool get isNotEmpty => _data.isNotEmpty;
 }
 
 // Private class used to manage all the active sessions. The sessions are stored
 // in two ways:
 //
 //  * In a map, mapping from ID to HttpSession.
 //  * In a linked list, used as a timeout queue.
 class _HttpSessionManager {
   _HttpSessionManager() : _sessions = {};
 
@@ skipping 94 matching lines @@
     }
   }
 
   Map<String, _HttpSession> _sessions;
   int _sessionTimeout = 20 * 60;  // 20 mins.
   _HttpSession _head;
   _HttpSession _tail;
   Timer _timer;
 }