[DRAFT] Create RenderFrameHostManager.

content/browser/loader/resource_loader.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/loader/resource_loader.h"
 
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/time/time.h"
@@ skipping 142 matching lines @@
       handler_->OnUploadProgress(
           info->GetRequestID(), progress.position(), progress.size());
       waiting_for_upload_progress_ack_ = true;
     }
     last_upload_ticks_ = TimeTicks::Now();
     last_upload_position_ = progress.position();
   }
 }
 
 void ResourceLoader::MarkAsTransferring(const GURL& target_url) {
-  CHECK_EQ(GetRequestInfo()->GetResourceType(), ResourceType::MAIN_FRAME)
-      << "Cannot transfer non-main frame navigations";
+  // TODO(creis): Why was this check here?  Is it a problem for cookies?

[davidben, 2013/11/18 22:20:50]

I actually came across that line some time ago and looked into this.

It's from http://crrev.com/217113. For sub-frames, set_first_party_for_cookies
probably shouldn't get called because an frame's first-party for cookies should
still be the top-level frame or something like that? Hence the MAIN_FRAME check.

I think neither that target_url parameter nor the set_first_party_for_cookies
call are needed anymore anyway. There is another set_first_party_for_cookies
call in AsyncResourceHandler that comes from the renderer, and the transfer
doesn't happen until after redirects are followed anyway. I never checked at
what point it stopped being necessary, but I would guess some combination of
when the handler chain stopped being rebuilt on transfers and when transfers
stopped happening at every redirect.

+  CHECK(GetRequestInfo()->GetResourceType() == ResourceType::MAIN_FRAME ||
+        GetRequestInfo()->GetResourceType() == ResourceType::SUB_FRAME)
+      << "Can only transfer navigations";
   is_transferring_ = true;
 
   // When transferring a request to another process, the renderer doesn't get
   // a chance to update the cookie policy URL. Do it here instead.
   request()->set_first_party_for_cookies(target_url);
 }
 
 void ResourceLoader::CompleteTransfer() {
   DCHECK_EQ(DEFERRED_READ, deferred_stage_);
 
@@ skipping 456 matching lines @@
       case net::URLRequestStatus::FAILED:
         status = STATUS_UNDEFINED;
         break;
     }
 
     UMA_HISTOGRAM_ENUMERATION("Net.Prefetch.Pattern", status, STATUS_MAX);
   }
 }
 
 }  // namespace content