Add chrome://proximity-auth UI implemented with Polymer.

components/proximity_auth/webui/resources/device-list.js

+// Copyright 2015 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('device-list', {
+  publish: {
+    /**
+     * The label of the list to be displayed.
+     * @type {string}
+     */
+    label: 'Device List',
+
+    /**
+     * Info of the devices contained in the list.
+     * @type {Array.<DeviceInfo>}
+     */
+    devices: null
+  },
+
+  /**
+   * Called when an instance is created.
+   */
+  created: function() {
+    this.devices = [];
+  },
+
+  /**
+   * @param {string} reason The device ineligibility reason.
+   * @return {string} The prettified ineligibility reason.
+   * @private
+   */
+  prettifyReason_: function(reason) {
+    if (reason == null)
+      return '';
+    var reasonWithSpaces = reason.replace(/([A-Z])/g, ' $1');
+    return reasonWithSpaces[0].toUpperCase() + reasonWithSpaces.slice(1);
+  },
+
+  /**
+   * @param {string} connectionStatus The Bluetooth connection status.
+   * @return {string} The icon id to be shown for the connection state.
+   * @private
+   */
+  getIconForConnection_: function(connectionStatus) {
+    switch (connectionStatus) {
+      case 'connected':
+        return 'device:bluetooth-connected';
+      case 'disconnected':
+        return 'device:bluetooth';
+      case 'connecting':
+        return 'device:bluetooth-searching';
+      default:
+        return 'device:bluetooth-disabled';
+    }
+  },
+
+  /**
+   * @param {string} reason The device ineligibility reason.
+   * @return {string} The icon id to be shown for the ineligibility reason.
+   * @private
+   */
+  getIconForIneligibilityReason_: function(reason) {
+    switch (reason) {
+      case 'badOsVersion':
+        return 'notification:system-update';
+      case 'bluetoothNotSupported':
+        return 'device:bluetooth-disabled';
+      case 'deviceOffline':
+        return 'device:signal-cellular-off';
+      case 'invalidCredentials':
+        return 'notification:sync-problem';
+      default:
+        return 'error';
+    };
+  }
+});