Simplify DownloadRequestHandle by using WebContentsGetter

content/browser/download/url_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 "content/browser/download/url_downloader.h"
 
 #include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/threading/sequenced_task_runner_handle.h"
@@ skipping 42 matching lines @@
         FROM_HERE, base::Bind(&UrlDownloader::PauseRequest, downloader_));
   }
   void ResumeRequest() const override {
     downloader_task_runner_->PostTask(
         FROM_HERE, base::Bind(&UrlDownloader::ResumeRequest, downloader_));
   }
   void CancelRequest() const override {
     downloader_task_runner_->PostTask(
         FROM_HERE, base::Bind(&UrlDownloader::CancelRequest, downloader_));
   }
-  std::string DebugString() const override { return std::string(); }
 
  private:
   base::WeakPtr<UrlDownloader> downloader_;
   base::WeakPtr<DownloadManagerImpl> download_manager_impl_;
   scoped_refptr<base::SequencedTaskRunner> downloader_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(RequestHandle);
 };
 
 // static
@@ skipping 176 matching lines @@
   Destroy();
 }
 
 void UrlDownloader::Destroy() {
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
       base::Bind(&DownloadManagerImpl::RemoveUrlDownloader, manager_, this));
 }
 
 }  // namespace content