Issue #1775488 by amateescu, vijaycs85: Fixed drupal_cron_cleanup() is not converted to lock.

core/includes/common.inc

@@ -4927,8 +4927,6 @@ function drupal_cron_run() {
         queue($queue_name)->createQueue();
       }
     }
-    // Register shutdown callback.
-    drupal_register_shutdown_function('drupal_cron_cleanup');
 
     // Iterate through the modules calling their cron handlers (if any):
     foreach (module_implements('cron') as $module) {
@@ -4970,22 +4968,6 @@ function drupal_cron_run() {
   return $return;
 }
 
-/**
- * Shutdown function: Performs cron cleanup.
- *
- * @see drupal_cron_run()
- * @see drupal_register_shutdown_function()
- */
-function drupal_cron_cleanup() {
-  // See if the semaphore is still locked.
-  if (variable_get('cron_semaphore', FALSE)) {
-    watchdog('cron', 'Cron run exceeded the time limit and was aborted.', array(), WATCHDOG_WARNING);
-
-    // Release cron semaphore.
-    variable_del('cron_semaphore');
-  }
-}
-
 /**
  * This function is kept only for backward compatibility.
  *