Make get_quick_select_for_ref() accept estimated # records as parameter and 
set QUICK_RANGE_SELECT::records, as this value is used to allocate buffers 
in Multi-Range Read. 


sql/opt_range.cc:
  Make get_quick_select_for_ref() accept estimated # records as parameter and 
  set QUICK_RANGE_SELECT::records, as this value is used to allocate buffers 
  in Multi-Range Read.
sql/opt_range.h:
  Added "records" parameter to get_quick_select_for_ref()
sql/sql_select.cc:
  Added "records" parameter to get_quick_select_for_ref()