'CREATE TABLE IF NOT EXISTS ... SELECT' statement were causing 'CREATE
TEMPORARY TABLE ...' to be written to the binary log in row-based 
mode (a.k.a. RBR), when there was a temporary table with the same name.
Because the 'CREATE TABLE ... SELECT' statement was executed as 
'INSERT ... SELECT' into the temporary table. Since in RBR mode no 
other statements related to temporary tables are written into binary log,
this sometimes broke replication.

This patch changes behavior of 'CREATE TABLE [IF NOT EXISTS] ... SELECT ...'.
it ignores existence of temporary table with the 
same name as table being created and is interpreted
as attempt to create/insert into base table. This makes behavior of
'CREATE TABLE [IF NOT EXISTS] ... SELECT' consistent with
how ordinary 'CREATE TABLE' and 'CREATE TABLE ... LIKE' behave.