Remove WebHistoryItem child usage

content/renderer/history_entry.cc

Index: content/renderer/history_entry.cc
diff --git a/content/renderer/history_entry.cc b/content/renderer/history_entry.cc
index 8d168ee5d3a4df9e88d1ec3a1cecd3c308a741ff..63c1ea0f1d3d588bde9a13ecb150b71065a2f955 100644
--- a/content/renderer/history_entry.cc
+++ b/content/renderer/history_entry.cc
@@ -35,8 +35,6 @@
 
 #include "content/renderer/history_entry.h"
 
-#include <deque>
-
 #include "content/renderer/render_frame_impl.h"
 #include "content/renderer/render_view_impl.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
@@ -53,6 +51,10 @@ HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::AddChild(
   return children_->back();
 }
 
+HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::AddChild() {
+  return AddChild(WebHistoryItem(), kInvalidFrameRoutingID);
+}
+
 HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::CloneAndReplace(
     HistoryEntry* new_entry,
     const WebHistoryItem& new_item,
@@ -90,13 +92,21 @@ HistoryEntry::HistoryNode* HistoryEntry::HistoryNode::CloneAndReplace(
   return new_history_node;
 }
 
+void HistoryEntry::HistoryNode::set_item(const WebHistoryItem& item) {
+  // The previous HistoryItem might not have had a target set, or it might be
+  // different than the current one.
+  entry_->unique_names_to_items_[item.target().utf8()] = this;
+  item_ = item;
+}
+
 HistoryEntry::HistoryNode::HistoryNode(HistoryEntry* entry,
                                        const WebHistoryItem& item,
                                        int64_t frame_id)
     : entry_(entry), item_(item) {
   if (frame_id != kInvalidFrameRoutingID)
     entry_->frames_to_items_[frame_id] = this;
-  entry_->unique_names_to_items_[item.target().utf8()] = this;
+  if (!item.isNull())
+    entry_->unique_names_to_items_[item.target().utf8()] = this;
   children_.reset(new ScopedVector<HistoryNode>);
 }
 
@@ -138,6 +148,7 @@ void HistoryEntry::HistoryNode::RemoveChildren() {
 }
 
 HistoryEntry::HistoryEntry() {
+  root_.reset(new HistoryNode(this, WebHistoryItem(), kInvalidFrameRoutingID));
 }
 
 HistoryEntry::~HistoryEntry() {