restores from mysqlbinlog out

Problem: using "mysqlbinlog | mysql" for recoveries the connection_id() 
result may differ from what was used when issuing the statement.

Fix: if there is a connection_id() in a statement, write to binlog
SET pseudo_thread_id= XXX; before it and use the value later on.


mysql-test/r/mysqlbinlog.result:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - test result.
mysql-test/t/mysqlbinlog.test:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - test case.
sql/item_create.cc:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - set thread_specific_used flag for the connection_id() function.
sql/item_func.cc:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - always return thd->variables.pseudo_thread_id as a connection_id() 
  result, as it contains a proper value for both master and slave.
sql/log_event.cc:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - set LOG_EVENT_THREAD_SPECIFIC_F event flag if thread_specific_used
  is set.
sql/sql_class.cc:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - thd->thread_specific_used introduced, which is set if thread specific 
  value(s) used in a statement.
sql/sql_class.h:
  Fix for bug #29928: INSERT ... VALUES(connection_id(), ...) incorrect 
  restores from mysqlbinlog out
    - thd->thread_specific_used introduced, which is set if thread specific 
  value(s) used in a statement.