Add support to specify the source address for socket connect

runtime/bin/eventhandler_win.h

Index: runtime/bin/eventhandler_win.h
diff --git a/runtime/bin/eventhandler_win.h b/runtime/bin/eventhandler_win.h
index 3a9a1f4b1c3e65d1a4381aded37ddded5911e0b5..b2c55116e3994c7e9483a3ef67fb40ee607bf514 100644
--- a/runtime/bin/eventhandler_win.h
+++ b/runtime/bin/eventhandler_win.h
@@ -469,6 +469,10 @@ class ClientSocket : public SocketHandle {
   }
   bool is_connected() const { return connected_; }
 
+  void mark_closed() {
+    closed_ = true;
+  }
+
  private:
   bool LoadDisconnectEx();