Extensions Docs Server: Proper path handling

chrome/common/extensions/docs/server2/static/js/branch.js

Index: chrome/common/extensions/docs/server2/static/js/branch.js
diff --git a/chrome/common/extensions/docs/server2/static/js/branch.js b/chrome/common/extensions/docs/server2/static/js/branch.js
index 3efea694089790ac3f453b6a3a2e3072f0173525..f435872927241dd861109234f99d6f04f50834af 100644
--- a/chrome/common/extensions/docs/server2/static/js/branch.js
+++ b/chrome/common/extensions/docs/server2/static/js/branch.js
@@ -9,12 +9,14 @@
       return;
     var current_branch = window.bootstrap.branchInfo.current;
     var path = window.location.pathname.split('/');
+    if (path[0] == '')
+      path = path.slice(1);
     var index = path.indexOf(current_branch);
     if (index != -1)
       path[index] = value;
     else
-      path.splice(path.length - 1, 0, value);
-    window.location = path.join('/');
+      path.splice(0, 0, value);
+    window.location = '/' + path.join('/');
   }
 
   document.getElementById('branchChooser').addEventListener(