* Added Item_ref::set_properties 
 * Item_ref::Item_ref now expects to get in *item either
     NULL - then fix_fields() will be called later  or 
     ptr to Item it will refer to - then an equivalent of fix_fields() call is performed


sql/item.cc:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Added Item_ref::set_properties 
   * Adjusted Item_ref::Item_ref calls to match new calling convention
sql/item.h:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Added Item_ref::set_properties 
   * Item_ref::Item_ref now expects to get in *item either
       NULL - then fix_fields() will be called later or
       ptr to Item it will refer to - then an equivalent of fix_fields() call is performed
sql/item_cmpfunc.cc:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Adjusted Item_ref::Item_ref calls to match new calling convention
sql/item_func.cc:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Added Item_ref::set_properties 
   * Adjusted Item_ref::Item_ref calls to match new calling convention
sql/item_row.cc:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Added Item_ref::set_properties 
   * Adjusted Item_ref::Item_ref calls to match new calling convention
sql/item_strfunc.cc:
  Merge of fix for BUG#6976 continued: pulling in some Item_ref changes from 5.0
   * Added Item_ref::set_properties 
   * Adjusted Item_ref::Item_ref calls to match new calling convention