Typecheck chrome://bookmarks using Closure Compiler

chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js

Index: chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js
diff --git a/chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js b/chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js
index 0a94621a4649c57fd12bba04c0ecee2cdffe37d8..131fe48527877f66c44f3de83c3818db50d6daa2 100644
--- a/chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js
+++ b/chrome/browser/resources/bookmark_manager/js/bmm/bookmark_tree.js
@@ -15,20 +15,27 @@ cr.define('bmm', function() {
   /** @const */ var TreeItem = cr.ui.TreeItem;
 
   var treeLookup = {};
+
+  /**
+   * This variable is fake and used only to declare exported bmm.tree name.
+   * @suppress {suspiciousCode}

[Dan Beam, 2014/09/23 02:46:55]

same

[Vitaly Pavlenko, 2014/09/23 22:20:55]

Done.

+   */
   var tree;
 
   // Manager for persisting the expanded state.
-  var expandedManager = {
+  var expandedManager = /** @type {EventListener} */({
     /**
      * A map of the collapsed IDs.
      * @type {Object}
      */
-    map: 'bookmarkTreeState' in localStorage ?
-        JSON.parse(localStorage['bookmarkTreeState']) : {},
+    map: 'bookmarkTreeState' in window.localStorage ?
+        /** @type {Object} */(JSON.parse(
+            window.localStorage['bookmarkTreeState'])

[Dan Beam, 2014/09/23 02:46:55]

why can't we just make an alias, e.g.

  var localStorage = window.localStorage;

so we don't have to rewrite to window. everywhere?

[Vitaly Pavlenko, 2014/09/23 22:20:55]

Done.

+        ) : {},
 
     /**
      * Set the collapsed state for an ID.
-     * @param {string} The bookmark ID of the tree item that was expanded or
+     * @param {string} id The bookmark ID of the tree item that was expanded or
      *     collapsed.
      * @param {boolean} expanded Whether the tree item was expanded.
      */
@@ -80,10 +87,10 @@ cr.define('bmm', function() {
       var map = this.map;
       // Save in a timeout so that we can coalesce multiple changes.
       this.timer = setTimeout(function() {
-        localStorage['bookmarkTreeState'] = JSON.stringify(map);
+        window.localStorage['bookmarkTreeState'] = JSON.stringify(map);
       }, 100);
     }
-  };
+  });
 
   // Clean up once per session but wait until things settle down a bit.
   setTimeout(expandedManager.cleanUp.bind(expandedManager), 1e4);
@@ -131,12 +138,17 @@ cr.define('bmm', function() {
    *
    * @param {!cr.ui.TreeItem} parent The parent tree item.
    * @param {!cr.ui.TreeItem} treeItem The tree item to add.
-   * @param {Function=} f A function which gets called after the item has been
-   *     added at the right index.
+   * @param {Function=} opt_f A function which gets called after the item has
+   *     been added at the right index.
    */
   function addTreeItem(parent, treeItem, opt_f) {
     chrome.bookmarks.getChildren(parent.bookmarkNode.id, function(children) {
-      var index = children.filter(bmm.isFolder).map(function(item) {
+      var index = children.filter(
+          /**
+           * @type {function (BookmarkTreeNode, number,
+           *                  Array.<(BookmarkTreeNode)>)}
+           */(bmm.isFolder)
+      ).map(function(item) {

[Dan Beam, 2014/09/23 02:46:55]

use a temporary variable to keep the code pretty

[Vitaly Pavlenko, 2014/09/23 22:20:55]

Done.

         return item.id;
       }).indexOf(treeItem.bookmarkNode.id);
       parent.addAt(treeItem, index);
@@ -151,7 +163,7 @@ cr.define('bmm', function() {
    * Creates a new bookmark list.
    * @param {Object=} opt_propertyBag Optional properties.
    * @constructor
-   * @extends {HTMLButtonElement}
+   * @extends {cr.ui.Tree}
    */
   var BookmarkTree = cr.ui.define('tree');
 
@@ -172,6 +184,10 @@ cr.define('bmm', function() {
         treeItem.label = treeItem.bookmarkNode.title = changeInfo.title;
     },
 
+    /**
+     * @param {string} id
+     * @param {ReorderInfo} reorderInfo
+     */
     handleChildrenReordered: function(id, reorderInfo) {
       var parentItem = treeLookup[id];
       // The tree only contains folders.
@@ -190,6 +206,10 @@ cr.define('bmm', function() {
       }
     },
 
+    /**
+     * @param {string} id
+     * @param {MoveInfo} moveInfo
+     */
     handleMoved: function(id, moveInfo) {
       var treeItem = treeLookup[id];
       if (treeItem) {
@@ -262,7 +282,8 @@ cr.define('bmm', function() {
             hasDirectories = true;
             var item = new BookmarkTreeItem(bookmarkNode);
             parentTreeItem.add(item);

[Dan Beam, 2014/09/23 02:46:55]

var children = assert(bookmarkNode.children);
var anyChildren = buildTreeItems(item, children);

[Vitaly Pavlenko, 2014/09/23 22:20:55]

Done.

-            var anyChildren = buildTreeItems(item, bookmarkNode.children);
+            var anyChildren = buildTreeItems(item,
+                                             assert(bookmarkNode.children));
             item.expanded = anyChildren && expandedManager.get(bookmarkNode.id);
           }
         }