DRAFT CL: Add FrameNavigationEntry and track subframe session histories.

content/browser/frame_host/frame_navigation_entry.h

Index: content/browser/frame_host/frame_navigation_entry.h
diff --git a/content/browser/frame_host/frame_navigation_entry.h b/content/browser/frame_host/frame_navigation_entry.h
index 2d38a2533f1edb63b280e12f449cacbce0697cf7..49166c67375326c5b9f06da3ee2a866d4b73db0d 100644
--- a/content/browser/frame_host/frame_navigation_entry.h
+++ b/content/browser/frame_host/frame_navigation_entry.h
@@ -8,6 +8,7 @@
 #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 {
@@ -25,7 +26,7 @@ class CONTENT_EXPORT FrameNavigationEntry
     : public base::RefCounted<FrameNavigationEntry> {
  public:
   FrameNavigationEntry();
-  FrameNavigationEntry(SiteInstanceImpl* site_instance,
+  FrameNavigationEntry(SiteInstanceImpl* instance,
                        const GURL& url,
                        const Referrer& referrer);
 
@@ -33,6 +34,15 @@ class CONTENT_EXPORT FrameNavigationEntry
   // 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
@@ -51,6 +61,20 @@ class CONTENT_EXPORT FrameNavigationEntry
   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();
@@ -65,6 +89,10 @@ class CONTENT_EXPORT FrameNavigationEntry
   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);
 };