Convert SerialIoHandler to use buffer interfaces for I/O API methods.

device/serial/serial_connection.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_connection.h"
 
 #include "device/serial/serial_io_handler.h"
 
 namespace device {
 
 SerialConnection::SerialConnection(scoped_refptr<SerialIoHandler> io_handler)
     : io_handler_(io_handler) {
-  // TODO(sammc): Call io_handler_->Initialize() once we support send and recv.
 }
 
 SerialConnection::~SerialConnection() {
 }
 
 void SerialConnection::GetInfo(
     const mojo::Callback<void(serial::ConnectionInfoPtr)>& callback) {
   callback.Run(io_handler_->GetPortInfo());
 }
 
@@ skipping 12 matching lines @@
 void SerialConnection::GetControlSignals(
     const mojo::Callback<void(serial::DeviceControlSignalsPtr)>& callback) {
   callback.Run(io_handler_->GetControlSignals());
 }
 
 void SerialConnection::Flush(const mojo::Callback<void(bool)>& callback) {
   callback.Run(io_handler_->Flush());
 }
 
 }  // namespace device