Adds back BookmarkNode::IsVisible. Turns out we want to conditionally

chrome/test/data/extensions/api_test/bookmark_manager/edit_disabled/test.js

 // Copyright (c) 2011 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.
 
 // Bookmark Manager API test for Chrome.
 // browser_tests.exe --gtest_filter=ExtensionApiTest.BookmarkManagerEditDisabled
 
 const pass = chrome.test.callbackPass;
 const fail = chrome.test.callbackFail;
 const assertEq = chrome.test.assertEq;
 const assertFalse = chrome.test.assertFalse;
 const assertTrue = chrome.test.assertTrue;
 const bookmarks = chrome.bookmarks;
 const bookmarkManager = chrome.experimental.bookmarkManager;
 
 var ERROR = "Bookmark editing is disabled.";
 
 // Bookmark model within this test:
 //  <root>/
 //    Bookmarks Bar/
 //      Folder/
 //        "BBB"
 //      "AAA"
 //    Other Bookmarks/
-//    Mobile Bookmarks/
 
 var tests = [
   function verifyModel() {
     bookmarks.getTree(pass(function(result) {
       assertEq(1, result.length);
       var root = result[0];
-      assertEq(3, root.children.length);
+      assertEq(2, root.children.length);
       bar = root.children[0];
       assertEq(2, bar.children.length);
       folder = bar.children[0];
       aaa = bar.children[1];
       assertEq('Folder', folder.title);
       assertEq('AAA', aaa.title);
       bbb = folder.children[0];
       assertEq('BBB', bbb.title);
     }));
   },
@@ skipping 35 matching lines @@
   },
 
   function editDisabled() {
     bookmarkManager.canEdit(pass(function(result) {
       assertFalse(result, 'Should not be able to edit bookmarks');
     }));
   }
 ];
 
 chrome.test.runTests(tests);