DRAFT CL: Add FrameNavigationEntry and track subframe session histories.

content/browser/frame_host/frame_navigation_entry.cc

 // 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.
 
 #include "content/browser/frame_host/frame_navigation_entry.h"
 
 namespace content {
 
-FrameNavigationEntry::FrameNavigationEntry() {
+FrameNavigationEntry::FrameNavigationEntry()
+    : frame_tree_node_id_(-1),
+      item_sequence_number_(-1) {
 }
 
-FrameNavigationEntry::FrameNavigationEntry(SiteInstanceImpl* site_instance,
+FrameNavigationEntry::FrameNavigationEntry(SiteInstanceImpl* instance,
                                            const GURL& url,
                                            const Referrer& referrer)
-    : site_instance_(site_instance), url_(url), referrer_(referrer) {
+    : site_instance_(instance),
+      url_(url),
+      referrer_(referrer),
+      frame_tree_node_id_(-1),
+      item_sequence_number_(-1),
+      document_sequence_number_(-1) {
 }
 
 FrameNavigationEntry::~FrameNavigationEntry() {
 }
 
 FrameNavigationEntry* FrameNavigationEntry::Clone() const {
   FrameNavigationEntry* copy = new FrameNavigationEntry();
 
   copy->site_instance_ = site_instance_;
   copy->url_ = url_;
   copy->referrer_ = referrer_;
+  copy->page_state_ = page_state_;
+  copy->item_sequence_number_ = item_sequence_number_;
+  copy->document_sequence_number_ = document_sequence_number_;
 
   return copy;
 }
 
 }  // namespace content