DRAFT CL: Add FrameNavigationEntry and track subframe session histories.

content/browser/frame_host/frame_navigation_entry.h

 // Copyright 2015 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_FRAME_NAVIGATION_ENTRY_H_
 #define CONTENT_BROWSER_FRAME_HOST_FRAME_NAVIGATION_ENTRY_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "content/browser/site_instance_impl.h"
+#include "content/public/common/page_state.h"
 #include "content/public/common/referrer.h"
 
 namespace content {
 
 // Represents a session history item for a particular frame.
 //
 // This class is refcounted and can be shared across multiple NavigationEntries.
 // For now, it is owned by a single NavigationEntry and only tracks the main
 // frame.
 //
 // TODO(creis): In --site-per-process, fill in a tree of FrameNavigationEntries
 // in each NavigationEntry, one per frame.  FrameNavigationEntries may be shared
 // across NavigationEntries if the frame hasn't changed.
 class CONTENT_EXPORT FrameNavigationEntry
     : public base::RefCounted<FrameNavigationEntry> {
  public:
   FrameNavigationEntry();
-  FrameNavigationEntry(SiteInstanceImpl* site_instance,
+  FrameNavigationEntry(SiteInstanceImpl* instance,
                        const GURL& url,
                        const Referrer& referrer);
 
   // Creates a copy of this FrameNavigationEntry that can be modified
   // independently from the original.
   FrameNavigationEntry* Clone() const;
 
+  // The ID of the FrameTreeNode this is associated with, which does not change
+  // across process swaps or if the FrameTreeNode itself is deleted and later
+  // restored for a history navigation.
+  // TODO(creis): This should probably be set in the constructor.
+  void set_frame_tree_node_id(int frame_tree_node_id) {
+    frame_tree_node_id_ = frame_tree_node_id;
+  }
+  int frame_tree_node_id() const { return frame_tree_node_id_; }
+
   // The SiteInstance responsible for rendering this frame.  All frames sharing
   // a SiteInstance must live in the same process.  This is a refcounted pointer
   // that keeps the SiteInstance (not necessarily the process) alive as long as
   // this object remains in the session history.
   void set_site_instance(SiteInstanceImpl* site_instance) {
     site_instance_ = site_instance;
   }
   SiteInstanceImpl* site_instance() const { return site_instance_.get(); }
 
   // The actual URL loaded in the frame.  This is in contrast to the virtual
   // URL, which is shown to the user.
   void set_url(const GURL& url) { url_ = url; }
   const GURL& url() const { return url_; }
 
   // The referring URL.  Can be empty.
   void set_referrer(const Referrer& referrer) { referrer_ = referrer; }
   const Referrer& referrer() const { return referrer_; }
 
+  // Keeps track of where this entry belongs in the frame's session history.
+  void set_item_sequence_number(int64 item_sequence_number) {
+    item_sequence_number_ = item_sequence_number;
+  }
+  int64 item_sequence_number() { return item_sequence_number_; }
+  void set_document_sequence_number(int64 document_sequence_number) {
+    document_sequence_number_ = document_sequence_number;
+  }
+  int64 document_sequence_number() { return document_sequence_number_; }
+
+  // TODO(creis): Make these FrameState.
+  void set_page_state(const PageState& state) { page_state_ = state; }
+  const PageState& page_state() const { return page_state_; }
+
  private:
   friend class base::RefCounted<FrameNavigationEntry>;
   virtual ~FrameNavigationEntry();
 
   // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
   // For all new fields, update |Clone|.
   // TODO(creis): These fields have implications for session restore.  This is
   // currently managed by NavigationEntry, but the logic will move here.
   // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
 
   // See the accessors above for descriptions.
   scoped_refptr<SiteInstanceImpl> site_instance_;
   GURL url_;
   Referrer referrer_;
+  PageState page_state_;
+  int frame_tree_node_id_;
+  int64 item_sequence_number_;
+  int64 document_sequence_number_;
 
   DISALLOW_COPY_AND_ASSIGN(FrameNavigationEntry);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_FRAME_NAVIGATION_ENTRY_H_