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

content/browser/download/download_request_handle.cc

 // 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.
 
 #include "content/browser/download/download_request_handle.h"
 
 #include "base/bind.h"
 #include "base/strings/stringprintf.h"
 #include "content/browser/frame_host/navigator.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/browser_side_navigation_policy.h"
 
 namespace content {
 
-DownloadRequestHandle::~DownloadRequestHandle() {
-}
+DownloadRequestHandleInterface::~DownloadRequestHandleInterface() {}
+
+DownloadRequestHandle::~DownloadRequestHandle() {}
 
 DownloadRequestHandle::DownloadRequestHandle()
     : child_id_(-1),
       render_view_id_(-1),
       request_id_(-1),
       frame_tree_node_id_(-1) {
 }
 
 DownloadRequestHandle::DownloadRequestHandle(
     const base::WeakPtr<DownloadResourceHandler>& handler,
@@ skipping 82 matching lines @@
                             " child_id = %d"
                             " render_view_id = %d"
                             " request_id = %d"
                             "}",
                             child_id_,
                             render_view_id_,
                             request_id_);
 }
 
 }  // namespace content