[Dice] Parse the Dice response header

chrome/browser/loader/chrome_resource_dispatcher_host_delegate.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 "chrome/browser/loader/chrome_resource_dispatcher_host_delegate.h"
 
 #include <stdint.h>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 826 matching lines @@
   // the content area.
   //
   // For example, on Android, for users that are signed in to Chrome, the
   // identity is mirrored into the content area. To do so, Chrome appends a
   // X-Chrome-Connected header to all Gaia requests from a connected profile so
   // Gaia could return a 204 response and let Chrome handle the action with
   // native UI. The only exception is requests from gaia webview, since the
   // native profile management UI is built on top of it.
   signin::FixAccountConsistencyRequestHeader(
       request, redirect_url, io_data, info->GetChildID(), info->GetRouteID());
+#if !defined(OS_IOS) && !defined(OS_ANDROID)
+  signin::ProcessDiceResponseHeaderIfExists(request, io_data);

[msarda, 2017/06/12 11:52:21]

It looks like the Mirror response header (ManageAccounts) is processed when a
response is received - see
https://cs.chromium.org/chromium/src/chrome/browser/loader/chrome_resource_di...

Why do we need to process the Dice response header on a redirect? Do we also
need to process it on a response?

[droger, 2017/06/12 12:39:14]

The Dice header is only seen on redirects currently.

We could call the function on responses as well, if we want to catch it if Gaia
changes the flow on their end, but I don't know if this is needed.

[msarda, 2017/06/12 14:03:42]

I think we're basically adding too much logic for sign-in header processing in
ChromeResourceDispatcherHostDelegate, but I am not an owner of
ChromeResourceDispatcherHostDelegate, so I do not know how much they care about
this. It may be good to just call the sign-in header helper once from here and
the header helper to do whatever it needs to do when a redirect occurs. WDYT?

[droger, 2017/06/12 16:12:58]

I understand. I merged the Dice and Mirror function. That way, if we need to
change the behavior in the future, we should not need to touch this file again.

+#endif
 
   if (io_data->loading_predictor_observer()) {
     io_data->loading_predictor_observer()->OnRequestRedirected(
         request, redirect_url, info->GetWebContentsGetterForRequest());
   }
 
   if (io_data->policy_header_helper())
     io_data->policy_header_helper()->AddPolicyHeaders(redirect_url, request);
 }
 
@@ skipping 116 matching lines @@
             &ChromeResourceDispatcherHostDelegate::OnAbortedFrameLoad,
             base::Unretained(this), url, request_loading_time));
     return;
   }
 
   std::string metric_name = (request_loading_time.InMilliseconds() < 100 ?
       "Net.ErrAborted.Fast" : "Net.ErrAborted.Slow");
   rappor::SampleDomainAndRegistryFromGURL(
       g_browser_process->rappor_service(), metric_name, url);
 }