Remove WebHistoryItem child usage

content/renderer/history_entry.h

Index: content/renderer/history_entry.h
diff --git a/content/renderer/history_entry.h b/content/renderer/history_entry.h
index f8cc14d5d6b33667a98fec6b9372fa57e0a306c3..5c4467900ae4093c976c980af727a25508669353 100644
--- a/content/renderer/history_entry.h
+++ b/content/renderer/history_entry.h
@@ -38,6 +38,7 @@
 #include "base/containers/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
+#include "content/common/content_export.h"
 #include "third_party/WebKit/public/platform/WebURLRequest.h"
 #include "third_party/WebKit/public/web/WebHistoryItem.h"
 
@@ -51,7 +52,7 @@ class RenderViewImpl;
 
 const int kInvalidFrameRoutingID = -1;
 
-class HistoryEntry {
+class CONTENT_EXPORT HistoryEntry {
  public:
   class HistoryNode {
    public:
@@ -67,7 +68,7 @@ class HistoryEntry {
                                  RenderFrameImpl* target_frame,
                                  RenderFrameImpl* current_frame);
     blink::WebHistoryItem& item() { return item_; }
-    void set_item(const blink::WebHistoryItem& item) { item_ = item; }
+    void set_item(const blink::WebHistoryItem& item);
     std::vector<HistoryNode*>& children() const { return children_->get(); }
     void RemoveChildren();