Refactor AppendToFile and WriteFileDescriptor

chrome/browser/media_galleries/win/mtp_device_operations_util.cc

 // Copyright (c) 2013 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 "chrome/browser/media_galleries/win/mtp_device_operations_util.h"
 
 #include <portabledevice.h>
 
 #include <algorithm>
 
@@ skipping 374 matching lines @@
   // |optimal_transfer_size|). This indicates the end of the stream has been
   // reached.
   if (FAILED(hr))
     return 0U;
   DCHECK_GT(bytes_read, 0U);
   CHECK_LE(bytes_read, buffer.length());
   int data_len =
       base::checked_cast<int>(
           std::min(bytes_read,
                    base::checked_cast<DWORD>(buffer.length())));
-  if (base::AppendToFile(local_path, buffer.c_str(), data_len) != data_len)
-    return 0U;
-  return data_len;
+  return base::AppendToFile(local_path, buffer.c_str(), data_len) ? data_len
+                                                                  : 0;
 }
 
 base::string16 GetObjectIdFromName(IPortableDevice* device,
                                    const base::string16& parent_id,
                                    const base::string16& object_name) {
   MTPDeviceObjectEntries object_entries;
   if (!GetMTPDeviceObjectEntries(device, parent_id, object_name,
                                  &object_entries) ||
       object_entries.empty())
     return base::string16();
   // TODO(thestig): This DCHECK can fail. Multiple MTP objects can have
   // the same name. Handle the situation gracefully. Refer to crbug.com/169930
   // for more details.
   DCHECK_EQ(1U, object_entries.size());
   return object_entries[0].object_id;
 }
 
 }  // namespace media_transfer_protocol