Merge with 5.1

Fixed valgrind warnings found from running main.connect under valgrind


sql/sp_head.cc:
  Ensure that vcol_info is reset
sql/sql_acl.cc:
  Fixed usage of wrong memroot for password
sql/sql_yacc.yy:
  Ensure that vcol_info is reset

sql/sql_class.h

@@ -63,6 +63,7 @@ public:
   bool report_error(THD *thd);
   bool is_invalidated() const { return m_invalidated; }
   void reset_reprepare_observer() { m_invalidated= FALSE; }
+  Reprepare_observer() {}                     /* Remove gcc warning */
 private:
   bool m_invalidated;
 };
@@ -1117,6 +1118,7 @@ public:
     /* Ignore error */
     return TRUE;
   }
+  Dummy_error_handler() {}                    /* Remove gcc warning */
 };