1. Item now uses my_charset_bin by default,

not default_charset_into. It fixes the
problem that in some cases numbers where
treated as CHAR(N), not as BINARY(N), e.g.
wrong 'charsetnr' when sent to the client side.
2. IFNULL didn't aggregate argument charsets
and collations, so IFNULL(1,'a') produced
a CHAR(N). Now produces a BINARY(N).
3. SELECT PROCEDURE ANALIZE now returns
BINARY columns, which is much better than it worked
previously: CHAR with the default character set.
But in the future it's worth to fix the fields
'Field_name' and 'Optimal_fieldtype' to use UTF8,
and 'Min_value' and 'Max_value' to inherit their charsets
from the original items. But it is not important,
and BINARY(N) is OK for now.
4. Tests were fixed accordingly. No new tests were
made, as the old onces cover everything.


mysql-test/r/analyse.result:
  SELECT PROCEDURE ANALIZE now returns
  BINARY columns, which is much better than it worked
  previously: CHAR with the default character set.
  But in the future it's worth to fix the fields
  'Field_name' and 'Optimal_fieldtype' to use UTF8,
  and 'Min_value' and 'Max_value' to inherit their charsets
  from the original items. But it is not important,
  and BINARY(N) is OK for now.
mysql-test/r/case.result:
  Test fix according to the changes
mysql-test/r/metadata.result:
  Test fix according to the changes
mysql-test/r/ps_1general.result:
  Test fix according to the changes
mysql-test/r/ps_2myisam.result:
  Test fix according to the changes
mysql-test/r/ps_3innodb.result:
  Test fix according to the changes
mysql-test/r/ps_4heap.result:
  Test fix according to the changes
mysql-test/r/ps_5merge.result:
  Test fix according to the changes
mysql-test/r/ps_6bdb.result:
  Test fix according to the changes
mysql-test/r/ps_7ndb.result:
  Test fix according to the changes
mysql-test/r/union.result:
  Test fix according to the changes
sql/item.cc:
  Item is now BINARY by default
sql/item_cmpfunc.cc:
  IFNULL now collects arguments collations/charsets
  like other functions do.

mysql-test/r/union.result

@@ -554,7 +554,7 @@ aa
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `a` char(20) NOT NULL default ''
+  `a` binary(20) NOT NULL default ''
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 create table t1 SELECT 12 as a UNION select 12.2 as a;