Changes to add duration into history database.

chrome/browser/history/visit_database.h

Index: chrome/browser/history/visit_database.h
diff --git a/chrome/browser/history/visit_database.h b/chrome/browser/history/visit_database.h
index 7b21c8e709ac968ae0039ad0194df5b8daf2baf2..705d3c8a665e7bfe73b570b208fbc838ae159f8e 100644
--- a/chrome/browser/history/visit_database.h
+++ b/chrome/browser/history/visit_database.h
@@ -173,6 +173,12 @@ class VisitDatabase {
   void GetVisitsSource(const VisitVector& visits,
                        VisitSourceMap* sources);
 
+  // Update the visit_details table with the duration information.
+  bool UpdateVisitDetails(VisitID visit_id, const base::TimeDelta duration);
+
+  // Get the visit details about the given visits.
+  void GetVisitDetails(const VisitVector& visits, VisitDetailMap* details);
+
  protected:
   // Returns the database for the functions in this interface.
   virtual sql::Connection& GetDB() = 0;