MD Settings: Search Engine: Call iron-list notifyResize

chrome/browser/resources/settings/search_engines_page/search_engines_page.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.
 
 /**
  * @fileoverview 'settings-search-engines-page' is the settings page
  * containing search engines settings.
  */
 Polymer({
   is: 'settings-search-engines-page',
 
   behaviors: [WebUIListenerBehavior],
 
   properties: {
     /** @type {!Array<!SearchEngine>} */
     defaultEngines: {
       type: Array,
-      value: function() { return []; }
+      value: function() {
+        return [];
+      },
     },
 
     /** @type {!Array<!SearchEngine>} */
     otherEngines: {
       type: Array,
-      value: function() { return []; }
+      value: function() {
+        return [];
+      },
     },
 
     /** @type {!Array<!SearchEngine>} */
     extensions: {
       type: Array,
-      value: function() { return []; }
+      value: function() {
+        return [];
+      },
     },
 
     /** @private {boolean} */
     showAddSearchEngineDialog_: Boolean,
 
     /** @private {boolean} */
     showExtensionsList_: {
       type: Boolean,
       computed: 'computeShowExtensionsList_(extensions)',
     }
   },
 
+  observers: ['extensionsChanged_(extensions, showExtensionsList_)'],
+
   /** @override */
   ready: function() {
-    settings.SearchEnginesBrowserProxyImpl.getInstance().
-        getSearchEnginesList().then(this.enginesChanged_.bind(this));
+    settings.SearchEnginesBrowserProxyImpl.getInstance()
+        .getSearchEnginesList()

[dschuyler, 2016/09/01 23:21:50]

nit: How about moving this line up with the line above
(It looks like they may fit).

+        .then(this.enginesChanged_.bind(this));
     this.addWebUIListener(
         'search-engines-changed', this.enginesChanged_.bind(this));
   },
 
+  /** @private */
+  extensionsChanged_: function() {
+    if (this.showExtensionsList_)
+      this.$.extensions.notifyResize();
+  },
+
   /**
    * @param {!SearchEnginesInfo} searchEnginesInfo
    * @private
    */
   enginesChanged_: function(searchEnginesInfo) {
     this.defaultEngines = searchEnginesInfo['defaults'];
     this.otherEngines = searchEnginesInfo['others'];
     this.extensions = searchEnginesInfo['extensions'];

[Dan Beam, 2016/09/02 00:41:11]

doesn't this already accomplish what you're doing with notifyResize()?  directly
resetting this.extensions?

[Dan Beam, 2016/09/02 00:42:19]

oh, nevermind, this is when the list is unhidden.  ignore me

   },
 
   /** @private */
   onAddSearchEngineTap_: function() {
     this.showAddSearchEngineDialog_ = true;
     this.async(function() {
       var dialog = this.$$('settings-search-engine-dialog');
       // Register listener to detect when the dialog is closed. Flip the boolean
       // once closed to force a restamp next time it is shown such that the
       // previous dialog's contents are cleared.
       dialog.addEventListener('close', function() {
         this.showAddSearchEngineDialog_ = false;
       }.bind(this));
     }.bind(this));
   },
 
   /** @private */
   computeShowExtensionsList_: function() {
     return this.extensions.length > 0;
   },
 });