Clone the subframe FrameNavigationEntries for in-page navigations.

content/browser/frame_host/navigation_entry_impl.h

Index: content/browser/frame_host/navigation_entry_impl.h
diff --git a/content/browser/frame_host/navigation_entry_impl.h b/content/browser/frame_host/navigation_entry_impl.h
index 8aec8152ba7561bee1a805969ab86ce73b054a3b..bdf1f9277ff1d6dc405599310581d233467488a8 100644
--- a/content/browser/frame_host/navigation_entry_impl.h
+++ b/content/browser/frame_host/navigation_entry_impl.h
@@ -46,7 +46,8 @@ class CONTENT_EXPORT NavigationEntryImpl
     // NavigationEntries of the same tab.
     scoped_ptr<TreeNode> CloneAndReplace(
         FrameTreeNode* frame_tree_node,
-        FrameNavigationEntry* frame_navigation_entry) const;
+        FrameNavigationEntry* frame_navigation_entry,
+        bool clone_children_of_target) const;
 
     // Ref counted pointer that keeps the FrameNavigationEntry alive as long as
     // it is needed by this node's NavigationEntry.
@@ -139,7 +140,9 @@ class CONTENT_EXPORT NavigationEntryImpl
   // that shares the existing FrameNavigationEntries (for use within the same
   // tab) and one that draws them from a different pool (for use in a new tab).
   scoped_ptr<NavigationEntryImpl> CloneAndReplace(
-      FrameTreeNode* frame_tree_node, FrameNavigationEntry* frame_entry) const;
+      FrameTreeNode* frame_tree_node,
+      FrameNavigationEntry* frame_entry,
+      bool clone_children_of_target) const;
 
   // Helper functions to construct NavigationParameters for a navigation to this
   // NavigationEntry.
@@ -171,6 +174,10 @@ class CONTENT_EXPORT NavigationEntryImpl
   TreeNode* root_node() const {
     return frame_tree_.get();
   }
+  // TODO(creis): Avoid exposing this.
+  void set_root_node(scoped_ptr<TreeNode> root_node) {
+    frame_tree_ = root_node.Pass();
+  }
 
   // Finds the TreeNode associated with |frame_tree_node_id| to add or update
   // its FrameNavigationEntry.  A new FrameNavigationEntry is added if none