Replace URLDataSource::MessageLoopForRequestPath() with TaskRunnerForRequestPath().

chrome/browser/thumbnails/thumbnail_list_source.h

 // Copyright 2014 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 CHROME_BROWSER_THUMBNAILS_THUMBNAIL_LIST_SOURCE_H_
 #define CHROME_BROWSER_THUMBNAILS_THUMBNAIL_LIST_SOURCE_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 26 matching lines @@
 
   // content::URLDataSource implementation.
   std::string GetSource() const override;
   // Called on the IO thread.
   void StartDataRequest(
       const std::string& path,
       const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
       const content::URLDataSource::GotDataCallback& callback) override;
 
   std::string GetMimeType(const std::string& path) const override;
-  base::MessageLoop* MessageLoopForRequestPath(
+  scoped_refptr<base::SingleThreadTaskRunner> TaskRunnerForRequestPath(
       const std::string& path) const override;
   bool ShouldServiceRequest(const net::URLRequest* request) const override;
   bool ShouldReplaceExistingSource() const override;
 
  private:
   ~ThumbnailListSource() override;
 
   // Called on the IO thread.
   void OnMostVisitedURLsAvailable(
     const content::URLDataSource::GotDataCallback& callback,
     const history::MostVisitedURLList& mvurl_list);
 
   // ThumbnailService.
   scoped_refptr<thumbnails::ThumbnailService> thumbnail_service_;
 
   scoped_refptr<history::TopSites> top_sites_;
 
   // For callbacks may be run after destruction.
   base::WeakPtrFactory<ThumbnailListSource> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ThumbnailListSource);
 };
 
 
 #endif  // CHROME_BROWSER_THUMBNAILS_THUMBNAIL_LIST_SOURCE_H_