Separated into 3 commits for good luck. See r19775.

git-svn-id: https://develop.svn.wordpress.org/trunk@19776 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/functions.php

@@ -3660,7 +3660,8 @@ function wp_allowed_protocols() {
 }
 
 /**
- * Return a comma seperated string of functions that have been called to get to the current point in code.
+ * Return a comma separated string of functions that have been called to get to the current point in code.
+ *
  * @link http://core.trac.wordpress.org/ticket/19589
  * @since 3.4
  *
@@ -3697,4 +3698,4 @@ function wp_debug_backtrace_summary( $ignore_class = null, $skip_frames = 0, $pr
 		return join( ', ', array_reverse( $caller ) );
 	else
 		return $caller;
-}
+}