[Downloads] Factor out request handling logic between DRH and UD.

content/browser/download/download_request_handle.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 CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_
 #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
 #include "content/browser/download/download_resource_handler.h"
 #include "content/common/content_export.h"
 
 namespace content {
 class DownloadManager;
 class WebContents;
 
 // A handle used by the download system for operations on the URLRequest
 // or objects conditional on it (e.g. WebContentsImpl).
 // This class needs to be copyable, so we can pass it across threads and not
 // worry about lifetime or const-ness.
 //
 // DownloadRequestHandleInterface is defined for mocking purposes.
 class CONTENT_EXPORT DownloadRequestHandleInterface {
  public:
-  virtual ~DownloadRequestHandleInterface() {}
+  virtual ~DownloadRequestHandleInterface();
 
   // These functions must be called on the UI thread.
   virtual WebContents* GetWebContents() const = 0;
   virtual DownloadManager* GetDownloadManager() const = 0;
 
   // Pauses or resumes the matching URL request.
   virtual void PauseRequest() const = 0;
   virtual void ResumeRequest() const = 0;
 
   // Cancels the request.
@@ skipping 46 matching lines @@
   int request_id_;
 
   // PlzNavigate
   // The ID of the FrameTreeNode that started the download.
   int frame_tree_node_id_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_HANDLE_H_