Why overriding a method if the new one is exactly the same of the one

in the base class?

IPython/html/static/notebook/js/textcell.js

@@ -407,11 +407,6 b' var IPython = (function (IPython) {'
     };
 
 
-    HeadingCell.prototype.set_rendered = function (html) {
-        this.element.find("div.text_cell_render").html(html);
-    };
-
-
     HeadingCell.prototype.get_rendered = function () {
         var r = this.element.find("div.text_cell_render");
         return r.children().first().html();