Flesh out the location-page class to make it more general.

chrome/browser/resources/settings/languages_page/languages.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-languages' provides convenient access to
  * Chrome's language and input method settings.
  *
  * Instances of this element have a 'languages' property, which reflects the
  * current language settings. The 'languages' property is read-only, meaning
@@ skipping 174 matching lines @@
 /**
  * Singleton element created when settings-languages is registered.
  * Generates the languages model on start-up, and updates it whenever Chrome's
  * pref store and other settings change. These updates propagate to each
  * <settings-language> instance so that their 'languages' property updates
  * like any other Polymer property.
  */
 Polymer({
   is: 'settings-languages-singleton',
 
+  behaviors: [PrefsBehavior],
+
   properties: {
     /**
      * @type {LanguagesModel|undefined}
      */
     languages: {
       type: Object,
       notify: true,
     },
 
     /**
@@ skipping 193 matching lines @@
     for (var i = 0; i < this.languages.enabledLanguages.length; i++) {
       var translateCode = this.convertLanguageCodeForTranslate(
           this.languages.enabledLanguages[i].language.code);
       this.set(
           'languages.enabledLanguages.' + i + '.state.translateEnabled',
           !translateBlockedMap[translateCode]);
     }
   },
 
   /**
-   * Gets the pref at the given key. Asserts if the pref is not found.
-   * @param {string} key
-   * @return {!chrome.settingsPrivate.PrefObject}
-   */
-  getPref_: function(key) {
-    var pref = /** @type {!chrome.settingsPrivate.PrefObject} */(
-        this.get(key, this.prefs));
-    assert(typeof pref != 'undefined', 'Pref is missing: ' + key);
-    return pref;
-  },
-
-  /**
-   * Sets the value of the pref at the given key. Asserts if the pref is not
-   * found.
-   * @param {string} key
-   * @param {*} value
-   */
-  setPrefValue_: function(key, value) {
-    this.getPref_(key);
-    this.set('prefs.' + key + '.value', value);
-  },
-
-  /**
    * Deletes the given item from the pref at the given key if the item is found.
    * Asserts if the pref itself is not found or is not an Array type.
    * @param {string} key
    * @param {*} item
    */
   deletePrefItem_: function(key, item) {
     assert(this.getPref_(key).type == chrome.settingsPrivate.PrefType.LIST);
     this.arrayDelete('prefs.' + key + '.value', item);
   },
 
@@ skipping 137 matching lines @@
       // necessary as a language code for the Translate server.
       return languageCode;
     }
     if (main in kTranslateLanguageSynonyms)
       return kTranslateLanguageSynonyms[main];
 
     return main;
   },
 });
 })();