RSS feed should be hidden if comments are closed on a node

Problem/Motivation

The feed icon is currently displayed for all nodes where the comment setting is open or closed, but not hidden. I believe that the icon should only be displayed when the commetns are open.

RSS-feeds are intended to allow a user to keep track of changes. If the comments are closed (but still visible) then there will not be any update to the feed. Presenting an RSS-feed in this situation gives the user the expectation that the feed will have updates.

Proposed resolution

Change the function commentrss_node_feed_access to block access unless the comments are open. In commentrss.module, starting from line 95:

/**
 * Access callback; determines if the user can access a node's comment RSS.
 */
function commentrss_node_feed_access($node, $check_view_access = TRUE) {
  // Old line: 
  // return $node->comment != COMMENT_NODE_HIDDEN && variable_get('commentrss_node', TRUE) && user_access('access comments') && (!$check_view_access || node_access('view', $node));
  // Replaced by new line:
  return $node->comment == COMMENT_NODE_OPEN && variable_get('commentrss_node', TRUE) && user_access('access comments') && (!$check_view_access || node_access('view', $node));
}