Index: src/wp-includes/shortcodes.php
===================================================================
--- src/wp-includes/shortcodes.php	(revision 34707)
+++ src/wp-includes/shortcodes.php	(working copy)
@@ -443,7 +443,7 @@
  * @since 2.5.0
  *
  * @param string $text
- * @return array List of attributes and their value.
+ * @return array|string List of attribute values. Returns empty array if trim( $text ) == '""'. Returns empty string if trim( $text ) == ''.  All other situations are not empty().
  */
 function shortcode_parse_atts($text) {
 	$atts = array();