anchor.diff:    static const int DEFAULT_EVICTION_TIMEOUT = 60000;
     bool _closing = false;
   
  -  final Map<String, Queue<_HttpClientConnection>> _idleConnections
  -      = new Map<String, Queue<_HttpClientConnection>>();
  +  final Map<String, Set<_HttpClientConnection>> _idleConnections
  +      = new Map<String, Set<_HttpClientConnection>>();
     final Set<_HttpClientConnection> _activeConnections
         = new Set<_HttpClientConnection>();
     final List<_Credentials> _credentials = [];
  
positive.code:       int port = proxy.isDirect ? uriPort: proxy.port;
        String key = isSecure ? "ssh:$host:$port" : "$host:$port";
        if (_idleConnections.containsKey(key)) {
          var connection = _idleConnections[key].removeFirst();
          if (_idleConnections[key].isEmpty) {
            _idleConnections.remove(key);
          }
  
negative.code:     }
      // TODO(ajohnsen): Listen for socket close events.
      if (!_idleConnections.containsKey(connection.key)) {
        _idleConnections[connection.key] = new Set();
      }
      _idleConnections[connection.key].add(connection);
    }
  
    // Remove a closed connnection from the active set.
  