Add 80% and 250% zoom level to settings.

chrome/browser/resources/settings/appearance_page/appearance_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.
 
 /**
  * 'settings-appearance-page' is the settings page containing appearance
  * settings.
  *
  * Example:
  *
@@ skipping 66 matching lines @@
      */
     pageZoomOptions_: {
       readOnly: true,
       type: Array,
       value: [
         {value: 25, name: '25%'},
         {value: 33, name: '33%'},
         {value: 50, name: '50%'},
         {value: 67, name: '67%'},
         {value: 75, name: '75%'},
+        {value: 80, name: '80%'},
         {value: 90, name: '90%'},
         {value: 100, name: '100%'},
         {value: 110, name: '110%'},
         {value: 125, name: '125%'},
         {value: 150, name: '150%'},
         {value: 175, name: '175%'},
         {value: 200, name: '200%'},
+        {value: 250, name: '250%'},
         {value: 300, name: '300%'},
         {value: 400, name: '400%'},
         {value: 500, name: '500%'},
       ],
     },
 
     /** @private */
     themeSublabel_: String,
 
     /**
@@ skipping 112 matching lines @@
 
   /**
    * @param {boolean} bookmarksBarVisible if bookmarks bar option is visible.
    * @return {string} 'first' if the argument is false or empty otherwise.
    * @private
    */
   getFirst_: function(bookmarksBarVisible) {
     return !bookmarksBarVisible ? 'first' : '';
   }
 });