[fsp] Simplify aborting logic.

chrome/browser/chromeos/file_system_provider/throttled_file_system.cc

 // Copyright 2015 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/chromeos/file_system_provider/throttled_file_system.h"
 
 #include <limits>
 #include <vector>
 
 #include "base/files/file.h"
@@ skipping 39 matching lines @@
     int64 offset,
     int length,
     const ReadChunkReceivedCallback& callback) {
   return file_system_->ReadFile(file_handle, buffer, offset, length, callback);
 }
 
 AbortCallback ThrottledFileSystem::OpenFile(const base::FilePath& file_path,
                                             OpenFileMode mode,
                                             const OpenFileCallback& callback) {
   const size_t task_token = open_queue_->NewToken();
-  return open_queue_->Enqueue(
+  open_queue_->Enqueue(
       task_token,
       base::Bind(
           &ProvidedFileSystemInterface::OpenFile,
           base::Unretained(file_system_.get()),  // Outlives the queue.
           file_path, mode,
           base::Bind(&ThrottledFileSystem::OnOpenFileCompleted,
                      weak_ptr_factory_.GetWeakPtr(), task_token, callback)));
+  return base::Bind(&ThrottledFileSystem::Abort, weak_ptr_factory_.GetWeakPtr(),
+                    task_token);
 }
 
 AbortCallback ThrottledFileSystem::CloseFile(
     int file_handle,
     const storage::AsyncFileUtil::StatusCallback& callback) {
   return file_system_->CloseFile(
       file_handle,
       base::Bind(&ThrottledFileSystem::OnCloseFileCompleted,
                  weak_ptr_factory_.GetWeakPtr(), file_handle, callback));
 }
@@ skipping 96 matching lines @@
     const std::string& tag,
     const storage::AsyncFileUtil::StatusCallback& callback) {
   return file_system_->Notify(entry_path, recursive, change_type,
                               changes.Pass(), tag, callback);
 }
 
 base::WeakPtr<ProvidedFileSystemInterface> ThrottledFileSystem::GetWeakPtr() {
   return weak_ptr_factory_.GetWeakPtr();
 }
 
+void ThrottledFileSystem::Abort(int queue_token) {
+  open_queue_->Abort(queue_token);
+}
+
 void ThrottledFileSystem::OnOpenFileCompleted(int queue_token,
                                               const OpenFileCallback& callback,
                                               int file_handle,
                                               base::File::Error result) {
   open_queue_->Complete(queue_token);
 
   // If the file is opened successfully then hold the queue token until the file
   // is closed.
   if (result == base::File::FILE_OK)
     opened_files_[file_handle] = queue_token;
@@ skipping 15 matching lines @@
 
   const int queue_token = it->second;
   open_queue_->Remove(queue_token);
   opened_files_.erase(file_handle);
 
   callback.Run(result);
 }
 
 }  // namespace file_system_provider
 }  // namespace chromeos