Bug 21982: Circulation statistics wizard does not count deleted items

By default statistic assistant filter is set on the
existing items and doesn't mind about deleted items.
The patch corrects this. Items belong to the same library.

Test plan:
1)Make sure to have at least 1 or more item(s) in deleteditems database table
2)Home > Reports > Circulation statistics
3)Fill up 'Issuing library', 'Home library' and 'Holding library'
4)Submit
5)Notice that only statistics for active items are shown
6)Apply patch and repeat from 2) to 5)
7)Now active items and deleted items are shown

Signed-off-by: Sally <sally.healey@cheshiresharedservices.gov.uk>

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 610f287db9)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
(cherry picked from commit c7b78eb133)
Signed-off-by: Arthur Suzuki <arthur.suzuki@biblibre.com>

reports/issues_stats.pl

@@ -506,7 +506,7 @@ sub calculate {
             $strcalc .= " LEFT JOIN borrower_attributes AS attribute_$_ ON (statistics.borrowernumber = attribute_$_.borrowernumber AND attribute_$_.code = '$_') ";
         }
     }
-    $strcalc .= "LEFT JOIN items ON statistics.itemnumber=items.itemnumber "
+    $strcalc .= "LEFT JOIN (SELECT * FROM items UNION SELECT * FROM deleteditems) items ON statistics.itemnumber=items.itemnumber "
       if ( $linefield =~ /^items\./
         or $colfield =~ /^items\./
         or $process == 5