Refactor the guts of ResourceDispatcherHostImpl into a new class named

content/browser/download/download_manager_impl.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_manager_impl.h"
 
 #include <iterator>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 35 matching lines @@
 using content::ResourceDispatcherHostImpl;
 using content::WebContents;
 
 namespace {
 
 void BeginDownload(content::DownloadUrlParameters* params) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   // ResourceDispatcherHost{Base} is-not-a URLRequest::Delegate, and
   // DownloadUrlParameters can-not include resource_dispatcher_host_impl.h, so
   // we must down cast. RDHI is the only subclass of RDH as of 2012 May 4.
-  content::ResourceDispatcherHostImpl* resource_dispatcher_host =
-    static_cast<content::ResourceDispatcherHostImpl*>(
-        params->resource_dispatcher_host());
   scoped_ptr<net::URLRequest> request(new net::URLRequest(
-      params->url(), resource_dispatcher_host));
+      params->url(), NULL));
   request->set_referrer(params->referrer().url.spec());
   webkit_glue::ConfigureURLRequestForReferrerPolicy(
       request.get(), params->referrer().policy);
   request->set_load_flags(request->load_flags() | params->load_flags());
   request->set_method(params->method());
   if (!params->post_body().empty())
     request->AppendBytesToUpload(params->post_body().data(),
                                  params->post_body().size());
   if (params->post_id() >= 0) {
     // The POST in this case does not have an actual body, and only works
     // when retrieving data from cache. This is done because we don't want
     // to do a re-POST without user consent, and currently don't have a good
     // plan on how to display the UI for that.
     DCHECK(params->prefer_cache());
     DCHECK(params->method() == "POST");
     scoped_refptr<net::UploadData> upload_data = new net::UploadData();
     upload_data->set_identifier(params->post_id());
     request->set_upload(upload_data);
   }
   for (content::DownloadUrlParameters::RequestHeadersType::const_iterator iter
            = params->request_headers_begin();
        iter != params->request_headers_end();
        ++iter) {
     request->SetExtraRequestHeaderByName(
         iter->first, iter->second, false/*overwrite*/);
   }
-  resource_dispatcher_host->BeginDownload(
+  params->resource_dispatcher_host()->BeginDownload(
       request.Pass(),
       params->content_initiated(),
       params->resource_context(),
       params->render_process_host_id(),
       params->render_view_host_routing_id(),
       params->prefer_cache(),
       params->save_info(),
       params->callback());
 }
 
@@ skipping 1079 matching lines @@
 void DownloadManagerImpl::DownloadRenamedToFinalName(
     DownloadItem* download) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   // If the rename failed, we receive an OnDownloadInterrupted() call before we
   // receive the DownloadRenamedToFinalName() call.
   if (delegate_) {
     delegate_->UpdatePathForItemInPersistentStore(
         download, download->GetFullPath());
   }
 }