Set network_accessed earlier, when network transaction creates stream.

net/url_request/url_request.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 "net/url_request/url_request.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ skipping 750 matching lines @@
   if (job) {
     RestartWithJob(job);
   } else if (delegate_) {
     OnCallToDelegate();
     delegate_->OnReceivedRedirect(this, redirect_info, defer_redirect);
     // |this| may be have been destroyed here.
   }
 }
 
 void URLRequest::NotifyBeforeNetworkStart(bool* defer) {
+  response_info_.network_accessed = true;

[davidben, 2015/05/04 17:57:19]

Why does this get set in two places and at two completely different layers? The
job overrides response_info_ at various points. Having this NotifyFoo function
go and overwrite whatever happens to be here right now seems clearly wrong.

If the problem is revalidations, the logic should be in HttpCache::Transaction.

+
   if (delegate_ && !notified_before_network_start_) {
     OnCallToDelegate();
     delegate_->OnBeforeNetworkStart(this, defer);
     if (!*defer)
       OnCallToDelegateComplete();
     notified_before_network_start_ = true;
   }
 }
 
 void URLRequest::ResumeNetworkStart() {
@@ skipping 399 matching lines @@
       new base::debug::StackTrace(NULL, 0);
   *stack_trace_copy = stack_trace;
   stack_trace_.reset(stack_trace_copy);
 }
 
 const base::debug::StackTrace* URLRequest::stack_trace() const {
   return stack_trace_.get();
 }
 
 }  // namespace net