Add support for custom entries in <cr_network_select/>.

ui/webui/resources/cr_elements/network/cr_network_list_custom_item.js

Index: ui/webui/resources/cr_elements/network/cr_network_list_custom_item.js
diff --git a/ui/webui/resources/cr_elements/network/cr_network_list_custom_item.js b/ui/webui/resources/cr_elements/network/cr_network_list_custom_item.js
new file mode 100644
index 0000000000000000000000000000000000000000..8b0115e676cf158d29b648469f058e6a03ee17d4
--- /dev/null
+++ b/ui/webui/resources/cr_elements/network/cr_network_list_custom_item.js
@@ -0,0 +1,85 @@
+// 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.
+
+/**
+ * @fileoverview Polymer element for displaying information about a network
+ * in a list or summary based on ONC state properties.
+ */
+(function() {
+'use strict';
+
+/**
+ * TODO(stevenjb): Replace getText with a proper localization function that
+ * handles string substitution.
+ * Performs argument substitution, replacing $1, $2, etc in 'text' with
+ * corresponding entries in |args|.
+ * @param {string} text The string to perform the substitution on.
+ * @param {?Array<string>=} opt_args The arguments to replace $1, $2, etc with.
+ */
+function getText(text, opt_args) {
+  var res;
+  if (loadTimeData && loadTimeData.data_)
+    res = loadTimeData.getString(text) || text;
+  else
+    res = text;
+  if (!opt_args)
+    return res;
+  for (let i = 0; i < opt_args.length; ++i) {
+    let key = '$' + (i + 1);
+    res = res.replace(key, opt_args[i]);
+  }
+  return res;
+}
+
+/**
+ * Polymer class definition for 'cr-network-list-custom-item'.
+ */
+Polymer({
+  is: 'cr-network-list-custom-item',
+
+  properties: {
+    /**
+     * Custom entry properties:
+     *   customItemName  - item name
+     *   polymerIcon     - item polymer icon
+     *   onTapEvent      - Event to send onTap
+     *                     (see <cr-network-select/> for details).
+     * @type {!Object}

[stevenjb, 2016/06/24 22:33:08]

Instead of commenting the properties like this, use closure notation to provide
a typedef, e.g. @type {CrNetworkListCustomItemState}. See cr_onc_types.js for a
bunch of typedef examples.

[Alexander Alekseev, 2016/06/25 06:04:43]

Done.

+     */
+    itemState: {
+      type: Object,
+      value: null,
+      observer: 'itemStateChanged_'
+    },
+  },
+
+  /**
+   * Polymer listeners.
+   */

[stevenjb, 2016/06/24 22:33:08]

nit: Comment not needed

[Alexander Alekseev, 2016/06/25 06:04:43]

Done.

+  listeners: {
+    'tap' : 'onTap_'
+  },
+
+  /**
+   * Polymer |itemState| changed method.
+   */
+  itemStateChanged_: function() {
+    if (!this.itemState)
+      return;
+
+    if (this.itemState.customItemName) {
+      this.$.itemName.textContent =
+          getText(this.itemState.customItemName);
+    }

[stevenjb, 2016/06/24 22:33:08]

This shouldn't be necessary, you can just use
[[getText(itemState.customItemName)]] in the HTML.

[Alexander Alekseev, 2016/06/25 06:04:43]

Done.

+  },
+

[stevenjb, 2016/06/24 22:33:08]

provide @param doc for |e|

[Alexander Alekseev, 2016/06/25 06:04:43]

Done.

+  onTap_: function(e) {
+    if (!this.itemState)
+      return;
+
+    if (this.itemState.onTapEvent)
+      this.fire(this.itemState.onTapEvent, this.itemState);

[stevenjb, 2016/06/24 22:33:08]

Instead of using a custom event, just fire e.g. 'network-custom-item-selected'.
The container can use itemState in the event handler to direct the behavior.

[Alexander Alekseev, 2016/06/25 06:04:43]

Done.

+  },
+});
+})();