Adds a textual css class for issue priorities (#12216).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@10720 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/issue.rb

@@ -906,7 +906,7 @@ class Issue < ActiveRecord::Base
 
   # Returns a string of css classes that apply to the issue
   def css_classes
-    s = "issue status-#{status_id} priority-#{priority_id}"
+    s = "issue status-#{status_id} #{priority.try(:css_classes)}"
     s << ' closed' if closed?
     s << ' overdue' if overdue?
     s << ' child' if child?