Ntp: restore scroll position.

content/public/browser/navigation_entry.h

Index: content/public/browser/navigation_entry.h
diff --git a/content/public/browser/navigation_entry.h b/content/public/browser/navigation_entry.h
index 87c17cd29e18c2dd566e6435cc46dbb6716c75d5..e39274ff4d8601c29611016feb4ec3a77aa9aebb 100644
--- a/content/public/browser/navigation_entry.h
+++ b/content/public/browser/navigation_entry.h
@@ -7,6 +7,7 @@
 
 #include <stdint.h>
 
+#include <map>
 #include <memory>
 #include <string>
 
@@ -205,6 +206,8 @@ class NavigationEntry {
   // If present, fills the |data| present at the specified |key|.
   virtual bool GetExtraData(const std::string& key,
                             base::string16* data) const = 0;
+  // Copies all extra data into |data|.
+  virtual void GetExtraData(std::map<std::string, base::string16>* data) = 0;
   // Removes the data at the specified |key|.
   virtual void ClearExtraData(const std::string& key) = 0;