Fix not to escape html in in-page headers (#10130)

layouts/docs/baseof.html

@@ -56,7 +56,7 @@
         headings.forEach(function(heading){
           if(heading.id){
             var a = document.createElement('a');
-            a.text = heading.innerHTML;
+            a.innerHTML = heading.innerHTML;
             a.href = '#'+heading.id;
             a.classList.add('inpage_heading');
             heading.innerHTML = '';