Move TransferNavigationResourceThrottle to content since that's where it belongs. This is a step in…

content/public/browser/resource_dispatcher_host_delegate.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_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 #pragma once
 
 #include <string>
 
@@ skipping 29 matching lines @@
   // Called when a request begins. Return false to abort the request.
   virtual bool ShouldBeginRequest(
       int child_id,
       int route_id,
       const std::string& method,
       const GURL& url,
       ResourceType::Type resource_type,
       ResourceContext* resource_context,
       const Referrer& referrer);
 
-  // Called after ShouldBeginRequest when all the resource handlers from the
-  // content layer have been added.  To add new handlers to the front, return
-  // a new handler that is chained to the given one, otherwise just reutrn the
-  // given handler.
+  // Called after ShouldBeginRequest to allow the embedder to add resource
+  // throttles.
   virtual void RequestBeginning(
       net::URLRequest* request,
       ResourceContext* resource_context,
       ResourceType::Type resource_type,
       int child_id,
       int route_id,
       bool is_continuation_of_transferred_request,
       ScopedVector<ResourceThrottle>* throttles);
 
   // Allows an embedder to add additional resource handlers for a download.
@@ skipping 51 matching lines @@
       ResourceResponse* response);
 
  protected:
   ResourceDispatcherHostDelegate();
   virtual ~ResourceDispatcherHostDelegate();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_