Fix aborting in throttled file system (FSP).

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 177 matching lines @@
 }
 
 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) {
-  if (result != base::File::FILE_ERROR_ABORT)
+  // The task may be aborted either via the callback, or by the operation, eg.
+  // because of destroying the request manager or unmounting the file system
+  // during the operation. Mark the task as completed only if it hasn't been
+  // aborted before.
+  if (!open_queue_->IsAborted(queue_token))
     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;
   else
     open_queue_->Remove(queue_token);
 
   callback.Run(file_handle, result);
@@ skipping 11 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