Add AnchorJS logic for header links (#10155)

* Add AnchorJS JavaScript

* Remove existing inpage_heading logic

* Remove underline from anchor tags

* Use single icon and add touch visibility

* Use paragraph link icon for AnchorJS

* Update Sass to use code formatting in docsContent headers

* Update header size coverage to H3-H6

layouts/docs/baseof.html

@@ -48,22 +48,5 @@
     </div>
 		{{ partialCached "footer.html" . }}
 		{{ partialCached "footer-scripts.html" . }}
-    <script>
-      // This script turns in-page headers into clickable and shareable
-      (function addHeadingLinks(){
-        var article = document.getElementById('docsContent');
-        var headings = article.querySelectorAll('h1, h2, h3, h4, h5, h6');
-        headings.forEach(function(heading){
-          if(heading.id){
-            var a = document.createElement('a');
-            a.innerHTML = heading.innerHTML;
-            a.href = '#'+heading.id;
-            a.classList.add('inpage_heading');
-            heading.innerHTML = '';
-            heading.appendChild(a);
-          }
-        });
-      })();
-    </script>
 	</body>
-</html>
+</html>