Applying InnoDB snashot 5.1-ss5282, Add TestCase for BUG#40565

Merge the test case from 5.0 to 5.1 for BUG#40565

Detailed revision comments:

r5233 | marko | 2009-06-03 15:12:44 +0300 (Wed, 03 Jun 2009) | 11 lines
branches/5.1: Merge the test case from r5232 from branches/5.0:
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  r5232 | marko | 2009-06-03 14:31:04 +0300 (Wed, 03 Jun 2009) | 21 lines

  branches/5.0: Merge r3590 from branches/5.1 in order to fix Bug #40565
  (Update Query Results in "1 Row Affected" But Should Be "Zero Rows").

  Also, add a test case for Bug #40565.

  rb://128 approved by Heikki Tuuri
  ------------------------------------------------------------------------

mysql-test/r/innodb_bug40565.result

+create table bug40565(value decimal(4,2)) engine=innodb;
+insert into bug40565 values (1), (null);
+update bug40565 set value=NULL;
+affected rows: 1
+info: Rows matched: 2  Changed: 1  Warnings: 0
+update bug40565 set value=NULL;
+affected rows: 0
+info: Rows matched: 2  Changed: 0  Warnings: 0
+drop table bug40565;

mysql-test/t/innodb_bug40565.test

+# Bug #40565 Update Query Results in "1 Row Affected" But Should Be "Zero Rows"
+-- source include/have_innodb.inc
+
+create table bug40565(value decimal(4,2)) engine=innodb;
+insert into bug40565 values (1), (null);
+--enable_info
+update bug40565 set value=NULL;
+update bug40565 set value=NULL;
+--disable_info
+drop table bug40565;