Removing file_thread_task_runner parameter from SerialIoHandler

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"
 
 #define INITGUID
 #include <devpkey.h>
 #include <setupapi.h>
 #include <windows.h>
@@ skipping 133 matching lines @@
 // Searches for the COM port in the device's friendly name, assigns its value to
 // com_port, and returns whether the operation was successful.
 bool GetCOMPort(const std::string friendly_name, std::string* com_port) {
   return RE2::PartialMatch(friendly_name, ".* \\((COM[0-9]+)\\)", com_port);
 }
 
 }  // namespace
 
 // static
 scoped_refptr<SerialIoHandler> SerialIoHandler::Create(
-    scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner) {
-  return new SerialIoHandlerWin(file_thread_task_runner, ui_thread_task_runner);
+  return new SerialIoHandlerWin(ui_thread_task_runner);
 }
 
 class SerialIoHandlerWin::UiThreadHelper final
     : public DeviceMonitorWin::Observer {
  public:
   UiThreadHelper(
       base::WeakPtr<SerialIoHandlerWin> io_handler,
       scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner)
       : device_observer_(this),
         io_handler_(io_handler),
@@ skipping 185 matching lines @@
   }
 
   if (!SetCommState(file().GetPlatformFile(), &config)) {
     VPLOG(1) << "Failed to set serial port info";
     return false;
   }
   return true;
 }
 
 SerialIoHandlerWin::SerialIoHandlerWin(
-    scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner)
-    : SerialIoHandler(file_thread_task_runner, ui_thread_task_runner),
+    : SerialIoHandler(ui_thread_task_runner),
       event_mask_(0),
       is_comm_pending_(false),
       helper_(nullptr),
       weak_factory_(this) {}
 
 SerialIoHandlerWin::~SerialIoHandlerWin() {
   ui_thread_task_runner()->DeleteSoon(FROM_HERE, helper_);
 }
 
 void SerialIoHandlerWin::OnIOCompleted(
@@ skipping 153 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