From 3772c10426254a72a2c835ef8a787da5315d52ff Mon Sep 17 00:00:00 2001
From: Trevor Parscal <tparscal@users.mediawiki.org>
Date: Sat, 14 May 2011 13:14:34 +0000
Subject: [PATCH] Improves on r88053 - added code basically lifted from
 jQuery.getScript which ensures that onreadystatechange is handled properly -
 only executing the callback when the state is changed to the correct state,
 and only calling it one time. Thanks John Resig!

---
 resources/mediawiki/mediawiki.js | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/resources/mediawiki/mediawiki.js b/resources/mediawiki/mediawiki.js
index 9fff95a5bd..f4f93f327d 100644
--- a/resources/mediawiki/mediawiki.js
+++ b/resources/mediawiki/mediawiki.js
@@ -933,7 +933,26 @@ window.mediaWiki = new ( function( $ ) {
 				script.setAttribute( 'src', src );
 				script.setAttribute( 'type', 'text/javascript' );
 				if ( $.isFunction( callback ) ) {
-					script.onload = script.onreadystatechange = callback;
+					var done = false;
+					// Attach handlers for all browsers -- this is based on jQuery.getScript
+					script.onload = script.onreadystatechange = function() {
+						if (
+							!done
+							&& (
+								!this.readyState
+								|| this.readyState === "loaded"
+								|| this.readyState === "complete"
+							)
+						) {
+							done = true;
+							callback();
+							// Handle memory leak in IE
+							script.onload = script.onreadystatechange = null;
+							if ( script.parentNode ) {
+								script.parentNode.removeChild( script );
+							}
+						}
+					};
 				}
 				document.body.appendChild( script );
 			} else {
-- 
2.20.1