Reverting a stray change. I blame the install system which insists I let that file be changed.

sites/default/settings.php

@@ -84,7 +84,7 @@
  *   $db_url = 'mysqli://username:password@localhost/databasename';
  *   $db_url = 'pgsql://username:password@localhost/databasename';
  */
-$db_url = 'mysql://drupal:drupal@localhost/c_drupal';
+$db_url = 'mysql://username:password@localhost/databasename';
 $db_prefix = '';
 
 /**