Index: src/wp-includes/l10n.php
===================================================================
--- src/wp-includes/l10n.php	(revision 28901)
+++ src/wp-includes/l10n.php	(working copy)
@@ -550,10 +550,12 @@
  * The .mo file should be named based on the text domain with a dash, and then the locale exactly.
  *
  * @since 1.5.0
+ * @since 2.8.0 Retruns a boolean value (before it did not return a value).
  *
  * @param string $domain          Unique identifier for retrieving translated strings
  * @param string $deprecated      Use the $plugin_rel_path parameter instead.
  * @param string $plugin_rel_path Optional. Relative path to WP_PLUGIN_DIR where the .mo file resides.
+ * @return bool True when textdomain is successfully loaded, false otherwise.
  */
 function load_plugin_textdomain( $domain, $deprecated = false, $plugin_rel_path = false ) {
 	$locale = get_locale();