WL#5370 Keep forward-compatibility when changing

        'CREATE TABLE IF NOT EXISTS ... SELECT' behaviour
BUG#47132, BUG#47442, BUG49494, BUG#23992 and BUG#48814 will disappear
automatically after the this patch.
BUG#55617 is fixed by this patch too.
            
This is the 5.5 part.
It implements:
- 'CREATE TABLE IF NOT EXISTS ... SELECT' statement will not insert
  anything and binlog anything if the table already exists.
  It only generate a warning that table already exists.
- A couple of test cases for the behavior changing.

1 files changed, 1 insertions, 1 deletions

diff --git a/mysql-test/r/auto_increment.result b/mysql-test/r/auto_increment.result
index 4a2e108f8c6..dbeedb481cd 100644
--- a/mysql-test/r/auto_increment.result
+++ b/mysql-test/r/auto_increment.result
@@ -469,7 +469,7 @@ drop table t1;
 CREATE TABLE t1 ( a INT );
 INSERT INTO t1 VALUES (1), (1);
 CREATE TABLE t2 ( a INT AUTO_INCREMENT KEY );
-CREATE TABLE IF NOT EXISTS t2 AS SELECT a FROM t1;
+INSERT INTO t2 SELECT a FROM t1;
 ERROR 23000: Duplicate entry '1' for key 'PRIMARY'
 UPDATE t2 SET a = 2;
 SELECT a FROM t2;