Remove handler from MessagePumpForIO::IOContext.

device/serial/serial_io_handler_win.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/serial/serial_io_handler_win.h"
 
 #include <windows.h>
 #include <setupapi.h>
 
 #include "base/bind.h"
@@ skipping 221 matching lines @@
 
 bool SerialIoHandlerWin::PostOpen() {
   DCHECK(!comm_context_);
   DCHECK(!read_context_);
   DCHECK(!write_context_);
 
   base::MessageLoopForIO::current()->RegisterIOHandler(file().GetPlatformFile(),
                                                        this);
 
   comm_context_.reset(new base::MessageLoopForIO::IOContext());
-  comm_context_->handler = this;
-  memset(&comm_context_->overlapped, 0, sizeof(comm_context_->overlapped));
-
   read_context_.reset(new base::MessageLoopForIO::IOContext());
-  read_context_->handler = this;
-  memset(&read_context_->overlapped, 0, sizeof(read_context_->overlapped));
-
   write_context_.reset(new base::MessageLoopForIO::IOContext());
-  write_context_->handler = this;
-  memset(&write_context_->overlapped, 0, sizeof(write_context_->overlapped));
 
   scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner =
       base::ThreadTaskRunnerHandle::Get();
   helper_ =
       new UiThreadHelper(weak_factory_.GetWeakPtr(), io_thread_task_runner);
   ui_thread_task_runner()->PostTask(
       FROM_HERE, base::Bind(&UiThreadHelper::Start, helper_));
 
   // A ReadIntervalTimeout of MAXDWORD will cause async reads to complete
   // immediately with any data that's available, even if there is none.
@@ skipping 272 matching lines @@
 std::string SerialIoHandler::MaybeFixUpPortName(const std::string& port_name) {
   // For COM numbers less than 9, CreateFile is called with a string such as
   // "COM1". For numbers greater than 9, a prefix of "\\\\.\\" must be added.
   if (port_name.length() > std::string("COM9").length())
     return std::string("\\\\.\\").append(port_name);
 
   return port_name;
 }
 
 }  // namespace device