Add path open errors from the permission broker to the device log.

device/serial/serial_io_handler.h

 // 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.
 
 #ifndef DEVICE_SERIAL_SERIAL_IO_HANDLER_H_
 #define DEVICE_SERIAL_SERIAL_IO_HANDLER_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
@@ skipping 32 matching lines @@
                     const serial::ConnectionOptions& options,
                     const OpenCompleteCallback& callback);
 
 #if defined(OS_CHROMEOS)
   // Signals that the port has been opened.
   void OnPathOpened(
       scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner,
       dbus::FileDescriptor fd);
 
+  // Signals that the permission broker failed to open the port.
+  void OnPathOpenError(
+      scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner,
+      const std::string& error_name,
+      const std::string& error_message);
+
   // Validates the file descriptor provided by the permission broker.
   void ValidateOpenPort(
       scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner,
       dbus::FileDescriptor fd);
+
+  // Reports the open error from the permission broker.
+  void ReportPathOpenError(const std::string& error_name,
+                           const std::string& error_message);
 #endif  // defined(OS_CHROMEOS)
 
   // Performs an async Read operation. Behavior is undefined if this is called
   // while a Read is already pending. Otherwise, the Done or DoneWithError
   // method on |buffer| will eventually be called with a result.
   void Read(scoped_ptr<WritableBuffer> buffer);
 
   // Performs an async Write operation. Behavior is undefined if this is called
   // while a Write is already pending. Otherwise, the Done or DoneWithError
   // method on |buffer| will eventually be called with a result.
@@ skipping 177 matching lines @@
   scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner_;
 
   std::string port_;
 
   DISALLOW_COPY_AND_ASSIGN(SerialIoHandler);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_SERIAL_SERIAL_IO_HANDLER_H_