Index: wp-admin/includes/class-wp-links-list-table.php
===================================================================
--- wp-admin/includes/class-wp-links-list-table.php	(revision 26234)
+++ wp-admin/includes/class-wp-links-list-table.php	(working copy)
@@ -175,6 +175,14 @@
 	 					?><td <?php echo $attributes ?>><?php echo $rating; ?></td><?php
 						break;
 					default:
+                                                /**
+                                                 * Fires for each registered custom link column.
+                                                 *
+                                                 * @since 2.1.0
+                                                 *
+                                                 * @param string $column_name   Name of the custom column.
+                                                 * @param int    $link_id       Link id.
+                                                 */
 						?>
 						<td <?php echo $attributes ?>><?php do_action( 'manage_link_custom_column', $column_name, $link->link_id ); ?></td>
 						<?php