Add test that passes invalid arguments to socket methods and fix

runtime/bin/socket_impl.dart

 // Copyright (c) 2012, 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.
 
 
 class _SocketBase {
   // Bit flags used when communicating between the eventhandler and
   // dart code. The EVENT flags are used to indicate events of
   // interest when sending a message from dart code to the
   // eventhandler. When receiving a message from the eventhandler the
@@ skipping 207 matching lines @@
           doReportError(new Exception("Unknown error"));
           break;
       }
     } else {
       doReportError(new SocketIOException(message));
     }
   }
 
   int hashCode() => _hashCode;
 
-  bool _propagateError(Exception e) => null;
+  bool _propagateError(Exception e) => false;
 
   abstract bool _isListenSocket();
   abstract bool _isPipe();
 
   // Socket id is set from native. -1 indicates that the socket was closed.
   int _id;
 
   // Dedicated ReceivePort for socket events.
   ReceivePort _handler;
 
@@ skipping 346 matching lines @@
   bool _seenFirstOutEvent = false;
   bool _pipe = false;
   Function _clientConnectHandler;
   Function _clientWriteHandler;
   SocketInputStream _inputStream;
   SocketOutputStream _outputStream;
   String _remoteHost;
   int _remotePort;
   static SendPort _socketService;
 }