Adding a trailing '/' to the doc switcher URL.

chrome/common/extensions/docs/js/bootstrap.js

+// Copyright (c) 2012 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.
+
 var fileXHREnabled = function() {
   var xhr = new XMLHttpRequest();
   try {
     xhr.onreadystatechange = function() {};
     xhr.onerror = function() {};
     xhr.open("GET", "nothing.xml", true);
     xhr.send(null);
   } catch (e) {
     return false;
   }
@@ skipping 58 matching lines @@
     if (currentBranch == '') {
       document.getElementById('unofficialWarning').style.display = 'block';
       document.getElementById('goToOfficialDocs').onclick = function() {
         location.href = officialURL;
       };
     } else if (currentBranch != 'stable') {
       document.getElementById("branchName").textContent =
           currentBranch.toUpperCase();
       document.getElementById('branchWarning').style.display = 'block';
       document.getElementById('branchChooser').onchange = function() {
-        location.href = officialURL + this.value;
+        location.href = officialURL + this.value + "/";
       };
     }
   }
 }