Merge with 4.0 for 4.1 release

Noteworthy:
- New HANDLER code
- New multi-update-grant-check code
- Table lock code in ha_innodb.cc was not applied

mysql-test/t/func_str.test

@@ -181,6 +181,13 @@ insert into t1 values ('one'),(NULL),('two'),('four');
 select a, quote(a), isnull(quote(a)), quote(a) is null, ifnull(quote(a), 'n') from t1;
 drop table t1;
 
+#
+# Bug #5498: TRIM fails with LEADING or TRAILING if remstr = str
+#
+
+select trim(trailing 'foo' from 'foo');
+select trim(leading 'foo' from 'foo');
+
 #
 # Test collation and coercibility
 #