deadlock in MYSQL_LOG::new_file()
style fixes


mysql-test/r/innodb.result:
  one more test for truncate
mysql-test/t/innodb.test:
  one more test for truncate
sql/ha_innodb.cc:
  bug#8151 - truncate leaves a transaction open
sql/handler.cc:
  bug#8151 - truncate leaves a transaction open
sql/item.h:
  style fix
sql/item_cmpfunc.cc:
  style fix
sql/item_cmpfunc.h:
  style fix
sql/item_func.cc:
  style fix
sql/item_func.h:
  style fix
sql/log.cc:
  let new_file() to lock LOCK_index,
  don't check for prepared_xids in rotate_and_purge()
  increase thread_safe_increment when LOCK_log is taken
sql/log_event.cc:
  mysqlbinlog now prints a warning if binlog was not closed properly
sql/sql_class.h:
  comments
sql/sql_repl.cc:
  DBUG_ENTER tag corrected