Rails3: use String#html_safe for principals_check_box_tags() at ApplicationHelper.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@6480 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/helpers/application_helper.rb

@@ -289,7 +289,7 @@ module ApplicationHelper
     principals.sort.each do |principal|
       s << "<label>#{ check_box_tag name, principal.id, false } #{h principal}</label>\n"
     end
-    s
+    s.html_safe
   end
 
   # Returns a string for users/groups option tags