net: Use SequencedTaskRunner for URLFetcherResponseWriter

net/url_request/url_fetcher.h

 // Copyright (c) 2012 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 NET_URL_REQUEST_URL_FETCHER_H_
 #define NET_URL_REQUEST_URL_FETCHER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/supports_user_data.h"
-#include "base/task_runner.h"
 #include "net/base/net_export.h"
 
 class GURL;
 
 namespace base {
 class FilePath;
 class MessageLoopProxy;
+class SequencedTaskRunner;
+class TaskRunner;
 class TimeDelta;
 }
 
 namespace net {
 class HostPortPair;
 class HttpRequestHeaders;
 class HttpResponseHeaders;
 class URLFetcherDelegate;
 class URLFetcherResponseWriter;
 class URLRequestContextGetter;
@@ skipping 191 matching lines @@
   virtual void SetAutomaticallyRetryOnNetworkChanges(int max_retries) = 0;
 
   // By default, the response is saved in a string. Call this method to save the
   // response to a file instead. Must be called before Start().
   // |file_task_runner| will be used for all file operations.
   // To save to a temporary file, use SaveResponseToTemporaryFile().
   // The created file is removed when the URLFetcher is deleted unless you
   // take ownership by calling GetResponseAsFilePath().
   virtual void SaveResponseToFileAtPath(
       const base::FilePath& file_path,
-      scoped_refptr<base::TaskRunner> file_task_runner) = 0;
+      scoped_refptr<base::SequencedTaskRunner> file_task_runner) = 0;
 
   // By default, the response is saved in a string. Call this method to save the
   // response to a temporary file instead. Must be called before Start().
   // |file_task_runner| will be used for all file operations.
   // The created file is removed when the URLFetcher is deleted unless you
   // take ownership by calling GetResponseAsFilePath().
   virtual void SaveResponseToTemporaryFile(
-      scoped_refptr<base::TaskRunner> file_task_runner) = 0;
+      scoped_refptr<base::SequencedTaskRunner> file_task_runner) = 0;
 
   // By default, the response is saved in a string. Call this method to use the
   // specified writer to save the response. Must be called before Start().
   virtual void SaveResponseWithWriter(
       scoped_ptr<URLFetcherResponseWriter> response_writer) = 0;
 
   // Retrieve the response headers from the request.  Must only be called after
   // the OnURLFetchComplete callback has run.
   virtual HttpResponseHeaders* GetResponseHeaders() const = 0;
 
@@ skipping 40 matching lines @@
   // be removed once the URLFetcher is destroyed.  User should not take
   // ownership more than once, or call this method after taking ownership.
   virtual bool GetResponseAsFilePath(
       bool take_ownership,
       base::FilePath* out_response_path) const = 0;
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_FETCHER_H_