MD Bookmarks: Proof-of-concept reimplementation of data storage/binding layer

chrome/browser/resources/md_bookmarks/item.js

 // Copyright 2016 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.
 
 Polymer({
   is: 'bookmarks-item',
 
+  behaviors: [
+    bookmarks.StoreClient,
+  ],
+
   properties: {
-    /** @type {BookmarkTreeNode} */
+    /** @type {BookmarkNode} */
     item: {
       type: Object,
       observer: 'onItemChanged_',
     },
 
+    itemId: {
+      type: String,
+      observer: 'updateFromStore',
+    },
+
     isFolder_: Boolean,
 
     isSelectedItem: {
       type: Boolean,
       reflectToAttribute: true,
     },
   },
 
   observers: [
     'updateFavicon_(item.url)',
   ],
 
   listeners: {
     'click': 'onClick_',
     'dblclick': 'onDblClick_',
   },
 
+  attached: function() {
+    this.observe('item', function(store) {
+      return store.nodes[this.itemId];
+    }.bind(this));
+    this.observe('isSelectedItem', function(store) {
+      return store.selection.items[this.itemId];
+    }.bind(this));
+
+    this.updateFromStore();
+  },
+
   /**
    * @param {Event} e
    * @private
    */
   onMenuButtonOpenClick_: function(e) {
     e.stopPropagation();
     this.fire('open-item-menu', {
       target: e.target,
       item: this.item,
     });
   },
 
   /** @private */
   onItemChanged_: function() {
     this.isFolder_ = !(this.item.url);
   },
 
   /**
    * @param {Event} e
    * @private
    */
   onClick_: function(e) {
-    this.fire('select-item', {
-      item: this.item,
-      range: e.shiftKey,
-      add: e.ctrlKey,
-    });
+    this.dispatch(bookmarks.actions.selectItem(
+        this.itemId, e.ctrlKey, e.shiftKey, this.getState()));
   },
 
   /**
    * @param {Event} e
    * @private
    */
   onDblClick_: function(e) {
     if (!this.item.url)
-      this.fire('selected-folder-changed', this.item.id);
+      this.dispatch(bookmarks.actions.selectFolder(this.item.id));
     else
       chrome.tabs.create({url: this.item.url});
   },
 
   /**
    * @param {string} url
    * @private
    */
   updateFavicon_: function(url) {
     this.$.icon.style.backgroundImage = cr.icon.getFavicon(url);
   },
 });