Clean patch with DCC static content

chrome/common/extensions/docs/static/js/article.js

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Scroll handling.
+//
+// Switches the sidebar between floating on the left and position:fixed
+// depending on whether it's scrolled into view, and manages the scroll-to-top
+// button: click logic, and when to show it.
+(function() {
+
+var isLargerThanMobile = window.matchMedia('screen and (min-width: 580px)').matches;
+
+var sidebar = document.querySelector('.inline-toc');
+var articleBody = document.querySelector('[itemprop="articleBody"]');
+
+
+function addPermalink(el) {
+  el.classList.add('has-permalink');
+  var id = el.id || el.textContent.toLowerCase().replace(' ', '-');
+  el.insertAdjacentHTML('beforeend',
+      '<a class="permalink" title="Permalink" href="#' + id + '">#</a>');
+}
+
+// Add permalinks to heading elements.
+function addPermalinkHeadings(container) {
+  if (container) {
+    ['h2','h3','h4'].forEach(function(h, i) {
+      [].forEach.call(container.querySelectorAll(h), addPermalink);
+    });
+  }
+}
+
+// Bomb out if we're not on an article page and have a TOC.
+if (!(sidebar && articleBody)) {
+  return;
+}
+
+if (isLargerThanMobile) {
+  var toc = sidebar.querySelector('#toc');
+  var offsetTop = sidebar.offsetParent.offsetTop
+
+  document.addEventListener('scroll', function(e) {
+    window.scrollY >= offsetTop ? sidebar.classList.add('sticky') :
+                                  sidebar.classList.remove('sticky');
+  });
+
+  toc.addEventListener('click', function(e) {
+    var parent = e.target.parentElement;
+    if (e.target.localName == 'a' && parent.classList.contains('toplevel')) {
+      // Allow normal link click if  h2 toplevel heading doesn't have h3s.
+      if (parent.querySelector('.toc')) {
+        e.preventDefault();
+        parent.classList.toggle('active');
+      }
+    }
+  });
+
+} else {
+  // Prevent permalinks from appearong on mobile.
+  document.body.classList.add('no-permalink');
+
+  articleBody.addEventListener('click', function(e) {
+    if (e.target.localName == 'h2') {
+      e.target.parentElement.classList.toggle('active');
+    }
+  });
+}
+
+addPermalinkHeadings(articleBody);
+
+}());