List custom fields fielters: multiple select filter wider (#15073).

Patch by Jérôme Bataille.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@12215 e93f8b46-1217-0410-a6f0-8f06a7374b81

public/javascripts/application.js

@@ -280,8 +280,13 @@ function toggleOperator(field) {
 function toggleMultiSelect(el) {
   if (el.attr('multiple')) {
     el.removeAttr('multiple');
+    el.attr('size', 1);
   } else {
     el.attr('multiple', true);
+    if (el.children().length > 10)
+      el.attr('size', 10);
+    else
+      el.attr('size', 4);
   }
 }