conditions.
When allocating memory for KEY_FIELD/SARGABLE_PARAM structures the
function update_ref_and_keys did not take into account the fact that
a single row equality could be replaced by several simple equalities.
Fixed by adjusting the counter cond_count accordingly for each subquery
when performing substitution of a row equality for simple equalities. 
 


mysql-test/r/row.result:
  Added a test case for bug #27154.
mysql-test/t/row.test:
  Added a test case for bug #27154.