Remove all remaining traces of MessageLoopProxy.

chrome/browser/net/file_downloader.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/net/file_downloader.h"
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
@@ skipping 15 matching lines @@
                                const DownloadFinishedCallback& callback)
     : callback_(callback),
       fetcher_(URLFetcher::Create(url, URLFetcher::GET, this)),
       local_path_(path),
       weak_ptr_factory_(this) {
   fetcher_->SetRequestContext(request_context);
   fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
                          net::LOAD_DO_NOT_SAVE_COOKIES);
   fetcher_->SetAutomaticallyRetryOnNetworkChanges(kNumRetries);
   fetcher_->SaveResponseToTemporaryFile(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
+      BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE));
 
   if (overwrite) {
     fetcher_->Start();
   } else {
     base::PostTaskAndReplyWithResult(
         BrowserThread::GetBlockingPool()
             ->GetTaskRunnerWithShutdownBehavior(
                 base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN)
             .get(),
         FROM_HERE, base::Bind(&base::PathExists, local_path_),
@@ skipping 48 matching lines @@
 }
 
 void FileDownloader::OnFileMoveDone(bool success) {
   if (!success) {
     DLOG(WARNING) << "Could not move file to "
                   << local_path_.LossyDisplayName();
   }
 
   callback_.Run(success ? DOWNLOADED : FAILED);
 }