Remove the sidebar flag from the feed definition returned by available_feeds and

replace with a type field with one of two values (head and block).  We need to
do this to determine what fields go in the rss block so we can ignore the
definitions that are related to the page head when creating the rss block that
goes into the sidebar.

modules/comment/helpers/comment_rss.php

@@ -21,10 +21,10 @@
 class comment_rss_Core {
   static function available_feeds($item) {
     return array(array("description" => t("All new comments"),
-                       "sidebar" => true,
+                       "type" => "block",
                        "uri" => "comments"),
                  array("description" => sprintf(t("Comments on %s"), $item->title),
-                       "sidebar" => true,
+                       "type" => "block",
                        "uri" => "comments/{$item->id}"));
   }