Navigation transitions: Block first response until after transitions have run.

content/browser/loader/cross_site_resource_handler.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_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_
 #define CONTENT_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "content/browser/loader/layered_resource_handler.h"
@@ skipping 35 matching lines @@
 
   // We can now send the response to the new renderer, which will cause
   // WebContentsImpl to swap in the new renderer and destroy the old one.
   void ResumeResponse();
 
   // When set to true, requests are leaked when they can't be passed to a
   // RenderViewHost, for unit tests.
   CONTENT_EXPORT static void SetLeakRequestsForTesting(
       bool leak_requests_for_testing);
 
+  // Navigations are deferred at OnResponseStarted to parse out any navigation
+  // transition link headers, and give the navigation transition (if it exists)
+  // a chance to run.
+  void ResumeResponseDeferredAtStart(int request_id);
+
+  // Returns whether the handler is deferred. This is designed for the
+  // browsertests.
+  bool is_deferred_for_testing() const { return did_defer_; }

[jam, 2014/06/11 02:00:21]

nit: name should be did_defer_for_testing. also no need for the second sentence
in the comment, if someone wants to find callers they can search for them

[shatch, 2014/06/14 00:41:37]

That variable is used internally to check if the request was already deferred
before resuming, the function was added to expose it for tests.

Removed the second sentence in the comment.

[jam, 2014/06/16 03:46:10]

per
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Function_Names,
this should be did_defer_for_testing()

[shatch, 2014/06/16 22:32:19]

Done.

+
  private:
   // Prepare to render the cross-site response in a new RenderViewHost, by
   // telling the old RenderViewHost to run its onunload handler.
   void StartCrossSiteTransition(int request_id,
                                 ResourceResponse* response,
                                 bool should_transfer);
 
   // Defer the navigation to the UI thread to check whether transfer is required
   // or not. Currently only used in --site-per-process.
   bool DeferForNavigationPolicyCheck(ResourceRequestInfoImpl* info,
                                      ResourceResponse* response,
                                      bool* defer);
 
+  bool OnNavigationTransitionResponseStarted(int request_id,
+                                             ResourceResponse* response,
+                                             bool* defer);
+
+  bool OnNormalResponseStarted(int request_id,
+                               ResourceResponse* response,
+                               bool* defer);
+
   void ResumeOrTransfer(bool is_transfer);
   void ResumeIfDeferred();
 
   // Called when about to defer a request.  Sets |did_defer_| and logs the
   // defferral
   void OnDidDefer();
 
   bool has_started_response_;
   bool in_cross_site_transition_;
   bool completed_during_transition_;
   bool did_defer_;
   net::URLRequestStatus completed_status_;
   std::string completed_security_info_;
   scoped_refptr<ResourceResponse> response_;
 
   // TODO(nasko): WeakPtr is needed in --site-per-process, since all navigations
   // are deferred to the UI thread and come back to IO thread via
   // PostTaskAndReplyWithResult. If a transfer is needed, it goes back to the UI
   // thread. This can be removed once the code is changed to only do one hop.
   base::WeakPtrFactory<CrossSiteResourceHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CrossSiteResourceHandler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_CROSS_SITE_RESOURCE_HANDLER_H_