PlzNavigate: store POST data in the FrameNavigationEntry

content/browser/frame_host/navigation_request.h

 // Copyright 2014 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_FRAME_HOST_NAVIGATION_REQUEST_H_
 #define CONTENT_BROWSER_FRAME_HOST_NAVIGATION_REQUEST_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 141 matching lines @@
   void CreateNavigationHandle(int pending_nav_entry_id);
 
   // Transfers the ownership of the NavigationHandle to |render_frame_host|.
   // This should be called when the navigation is ready to commit, because the
   // NavigationHandle outlives the NavigationRequest. The NavigationHandle's
   // lifetime is the entire navigation, while the NavigationRequest is
   // destroyed when a navigation is ready for commit.
   void TransferNavigationHandleOwnership(
       RenderFrameHostImpl* render_frame_host);
 
+  // Resets the POST data for the navigation. This is called when encoutering a
+  // cross-site redirect.
+  void ResetPostData();

[Charlie Reis, 2016/05/11 00:00:23]

Lukasz found some useful info on this in the spec (which is quite surprising to
me).  Apparently POST data is preserved on 307 and 308 redirects (which stay
POST), regardless of origin.  302, 303, and 304 redirects are converted to GET
and lose POST data.

While I think it's crazy that sites might pass on their POST data cross-site
without realizing it, we should probably preserve Chrome's current behavior here
(once we verify that this is true in practice).  Not sure what implication that
has for this method.

[clamy, 2016/05/11 08:54:41]

Removed the function, since the current behavior can be matched in
NavigationReques internally. We may reintroduce it if we decide to have POST
data be reset cross-site when --site-per-process is enabled.

+
  private:
   NavigationRequest(FrameTreeNode* frame_tree_node,
                     const CommonNavigationParams& common_params,
                     const BeginNavigationParams& begin_params,
                     const RequestNavigationParams& request_params,
                     scoped_refptr<ResourceRequestBody> body,
                     bool browser_initiated,
                     const FrameNavigationEntry* frame_navigation_entry,
                     const NavigationEntryImpl* navitation_entry);
 
@@ skipping 47 matching lines @@
 
   // These next items are used in browser-initiated navigations to store
   // information from the NavigationEntryImpl that is required after request
   // creation time.
   scoped_refptr<SiteInstanceImpl> source_site_instance_;
   scoped_refptr<SiteInstanceImpl> dest_site_instance_;
   NavigationEntryImpl::RestoreType restore_type_;
   bool is_view_source_;
   int bindings_;
 
+  // This is kept to be sent to the renderer on commit.
+  scoped_refptr<ResourceRequestBody> post_data_;
+
   // The type of SiteInstance associated with this navigation.
   AssociatedSiteInstanceType associated_site_instance_type_;
 
   std::unique_ptr<NavigationHandleImpl> navigation_handle_;
 
   // Holds the ResourceResponse and the StreamHandle for the navigation while
   // the WillProcessResponse checks are performed by the NavigationHandle.
   scoped_refptr<ResourceResponse> response_;
   std::unique_ptr<StreamHandle> body_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationRequest);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_REQUEST_H_