Add link to the Advanced Font Settings extension in Font Settings

chrome/browser/resources/options/font_settings.js

 // Copyright (c) 2012 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.
 
 cr.define('options', function() {
 
   var OptionsPage = options.OptionsPage;
 
   /**
    * FontSettings class
@@ skipping 39 matching lines @@
                       $('sans-serif-font-family'), $('fixed-font-family'),
                       $('font-encoding')];
       elements.forEach(function(el) {
         el.appendChild(new Option(placeholder));
         el.setDisabled('noFontsAvailable', true);
       });
 
       $('font-settings-confirm').onclick = function() {
         OptionsPage.closeOverlay();
       };
+
+      $('advanced-font-settings-options').onclick = function() {
+        chrome.send('openAdvancedFontSettingsOptions');
+      };
     },
 
     /**
      * Called by the options page when this page has been shown.
      */
     didShowPage: function() {
       // The fonts list may be large so we only load it when this page is
       // loaded for the first time.  This makes opening the options window
       // faster and consume less memory if the user never opens the fonts
       // dialog.
@@ skipping 157 matching lines @@
 
   FontSettings.setUpMinimumFontSample = function(size) {
     // If size is less than 6, represent it as six in the sample to account
     // for the minimum logical font size.
     if (size < 6)
       size = 6;
     FontSettings.getInstance().setUpFontSample_($('minimum-font-sample'), size,
                                                 null, true);
   };
 
+  /**
+   * @param {boolean} available Whether the Advanced Font Settings Extension
+   *     is installed and enabled.
+   */
+  FontSettings.notifyAdvancedFontSettingsAvailability = function(available) {
+    $('advanced-font-settings-install').hidden = available;
+    $('advanced-font-settings-options').hidden = !available;
+  };
+
   // Export
   return {
     FontSettings: FontSettings
   };
 });