Ensure that the DOM element ref in an event handler is removed by cleanData to...

Ensure that the DOM element ref in an event handler is removed by cleanData to avoid an IE6/7/8 memory leak. Fixes #7054.

src/manipulation.js

@@ -617,6 +617,11 @@ jQuery.extend({
 							jQuery.removeEvent( elem, type, data.handle );
 						}
 					}
+
+					// Null the DOM reference to avoid IE6/7/8 leak (#7054)
+					if ( data.handle ) {
+						data.handle.elem = null;
+					}
 				}
 
 				if ( deleteExpando ) {