Bug #27417 thd->no_trans_update.stmt lost value inside of SF-exec-stack
  
Once had been set the flag might later got reset inside of a stored routine 
execution stack.
The reason was in that there was no check if a new statement started at time 
of resetting.
The artifact affects most of binlogable DML queries. Notice, that multi-update 
is wrapped up within
  bug@27716 fix, multi-delete bug@29136.
  
Fixed with saving parent's statement flag of whether the statement modified 
non-transactional table, and unioning (merging) the value with that was gained 
in mysql_execute_command.
  
Resettling thd->no_trans_update members into thd->transaction.`member`;
Asserting code;
Effectively the following properties are held.
  
1. At the end of a substatement thd->transaction.stmt.modified_non_trans_table
   reflects the fact if such a table got modified by the substatement.
   That also respects THD::really_abort_on_warnin() requirements.
2. Eventually thd->transaction.stmt.modified_non_trans_table will be computed as
   the union of the values of all invoked sub-statements.
   That fixes this bug#27417;

Computing of thd->transaction.all.modified_non_trans_table is refined to base to 
the stmt's value for all the case including insert .. select statement which 
before the patch had an extra issue bug@28960.
Minor issues are covered with mysql_load, mysql_delete, and binloggin of insert in
to temp_table select. 
  
The supplied test verifies limitely, mostly asserts. The ultimate testing is defered
for bug@13270, bug@23333.