Dialog: Reduce old overlay dimensions to 0x0 to avoid sizing issues. …

…Fixes #5637 - Dialog: Dimensions of reused overlay may cause scrollbars.

ui/jquery.ui.dialog.js

@@ -742,7 +742,7 @@ $.extend( $.ui.dialog.overlay, {
 			$( [ document, window ] ).unbind( ".dialog-overlay" );
 		}
 
-		$el.remove();
+		$el.height( 0 ).width( 0 ).remove();
 
 		// adjust the maxZ to allow other modal dialogs to continue to work (see #4309)
 		var maxZ = 0;