Reapply "Fixes to eventhandler and HTTP""

runtime/bin/socket_patch.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.
 
 patch class ServerSocket {
   /* patch */ factory ServerSocket(String bindAddress, int port, int backlog) {
     return new _ServerSocket(bindAddress, port, backlog);
   }
 }
 
@@ skipping 48 matching lines @@
     _canActivateHandlers = false;
     for (int i = _FIRST_EVENT; i <= _LAST_EVENT; i++) {
       if (((event_mask & (1 << i)) != 0)) {
         if ((i == _CLOSE_EVENT) && this is _Socket && !_closed) {
           _closedRead = true;
           if (_closedWrite) _close();
         }
 
         var eventHandler = _handlerMap[i];
         if (eventHandler != null || i == _ERROR_EVENT) {
-          // Unregister the out handler before executing it.
-          if (i == _OUT_EVENT) _setHandler(i, null);
+          // Unregister the out handler before executing it. There is
+          // no need to notify the eventhandler as handlers are
+          // disabled while the event is handled.
+          if (i == _OUT_EVENT) _setHandler(i, null, notifyEventhandler: false);
 
           // Don't call the in handler if there is no data available
           // after all.
           if ((i == _IN_EVENT) && (this is _Socket) && (available() == 0)) {
             continue;
           }
           if (i == _ERROR_EVENT) {
             _reportError(_getError(), "");
             close();
           } else {
             eventHandler();
           }
         }
       }
     }
     _canActivateHandlers = true;
     _activateHandlers();
   }
 
-  void _setHandler(int event, Function callback) {
+  void _setHandler(int event,
+                   Function callback,
+                   {bool notifyEventhandler: true}) {
     if (callback == null) {
       _handlerMask &= ~(1 << event);
     } else {
       _handlerMask |= (1 << event);
     }
     _handlerMap[event] = callback;
     // If the socket is only for writing then close the receive port
     // when not waiting for any events.
     if (this is _Socket &&
         _closedRead &&
         _handlerMask == 0 &&
         _handler != null) {
       _handler.close();
       _handler = null;
     } else {
-      _activateHandlers();
+      if (notifyEventhandler) _activateHandlers();
     }
   }
 
   OSError _getError() native "Socket_GetError";
 
   int _getPort() native "Socket_GetPort";
 
   void set onError(void callback(e)) {
     _setHandler(_ERROR_EVENT, callback);
   }
@@ skipping 477 matching lines @@
   bool _seenFirstOutEvent = false;
   bool _pipe = false;
   Function _clientConnectHandler;
   Function _clientWriteHandler;
   _SocketInputStream _inputStream;
   _SocketOutputStream _outputStream;
   String _remoteHost;
   int _remotePort;
   static SendPort _socketService;
 }