Add support to specify the source address for socket connect

runtime/bin/eventhandler_win.h

 // 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.
 
 #ifndef BIN_EVENTHANDLER_WIN_H_
 #define BIN_EVENTHANDLER_WIN_H_
 
 #if !defined(BIN_EVENTHANDLER_H_)
 #error Do not include eventhandler_win.h directly; use eventhandler.h instead.
 #endif
@@ skipping 440 matching lines @@
   virtual bool IsClosed();
 
   ClientSocket* next() { return next_; }
   void set_next(ClientSocket* next) { next_ = next; }
 
   void mark_connected() {
     connected_ = true;
   }
   bool is_connected() const { return connected_; }
 
+  void mark_closed() {
+    closed_ = true;
+  }
+
  private:
   bool LoadDisconnectEx();
 
   LPFN_DISCONNECTEX DisconnectEx_;
   ClientSocket* next_;
   bool connected_;
   bool closed_;
 };
 
 
@@ skipping 53 matching lines @@
 
   TimeoutQueue timeout_queue_;  // Time for next timeout.
   bool shutdown_;
   HANDLE completion_port_;
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // BIN_EVENTHANDLER_WIN_H_