[MD Bookmarks] Add UI for Material Bookmarks.

chrome/browser/resources/md_bookmarks/folder_node.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-folder-node',
+
+  properties: {
+    /** @type {BookmarkTreeNode} */
+    item: Object,
+
+    isSelected: {
+      type: Boolean,
+      value: false,
+      reflectToAttribute: true,
+    },
+  },
+
+  /** @private */

[tsergeant, 2017/01/03 23:31:17]

@return annotation here and on the next function.

[jiaxi, 2017/01/04 02:50:16]

Done.

+  getFolderIcon_: function() {
+    return this.isSelected ? 'bookmarks:folder-open' : 'bookmarks:folder';
+  },
+
+  /** @private */
+  getArrowIcon_: function() {
+    return this.item.isOpen ? 'cr:arrow-drop-up' : 'cr:arrow-drop-down';

[tsergeant, 2017/01/03 23:31:17]

Did you deliberately leave out the change to cr_elements/icons.html from this
CL? (Chris?) It means that cr:arrow-drop-up doesn't exist and no icon appears.

If you want to avoid changing the shared file right now, add `arrow-drop-up` to
md_bookmarks/icons.html with a TODO to move it into the shared file.

[calamity, 2017/01/04 00:43:00]

Yeah, I'd rather not do all the settings stuff in this CL. Add the TODO for
folder too.

[jiaxi, 2017/01/04 02:50:16]

Done.

[jiaxi, 2017/01/04 02:50:16]

Done.

+  },
+
+  /** @private */
+  selectFolder_: function() {
+    this.fire('selected-folder-changed', this.item.id);
+  },
+
+  /**
+   * Occurs when the drop down arrow is tapped.
+   * @private
+   */
+  toggleFolder_: function() {
+    this.fire('folder-open-changed', {
+      id: this.item.id,
+      open: !this.item.isOpen,
+    });
+  },
+
+  /** @private */

[tsergeant, 2017/01/03 23:31:17]

@return annotation

[jiaxi, 2017/01/04 02:50:16]

Done.

+  hasChildFolder_: function() {
+    for (var i = 0; i < this.item.children.length; i++) {
+      if (!this.item.children[i].url) {

[tsergeant, 2017/01/03 23:31:17]

Remove {}

[jiaxi, 2017/01/04 02:50:16]

Done.

+        return true;
+      }
+    }
+    return false;
+  },
+});