Ability to sort issues by grouped column (#3511).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@10765 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/helpers/sort_helper.rb

@@ -89,6 +89,10 @@ module SortHelper
       sql.blank? ? nil : sql
     end
 
+    def to_a
+      @criteria.dup
+    end
+
     def add!(key, asc)
       @criteria.delete_if {|k,o| k == key}
       @criteria = [[key, asc]] + @criteria
@@ -182,6 +186,10 @@ module SortHelper
     @sort_criteria.to_sql
   end
 
+  def sort_criteria
+    @sort_criteria
+  end
+
   # Returns a link which sorts by the named column.
   #
   # - column is the name of an attribute in the sorted record collection.