MD Settings: Polish languages pages.

chrome/browser/resources/settings/languages_page/manage_languages_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-manage-languages-page' is a sub-page for enabling
  * and disabling languages.
  */
 Polymer({
   is: 'settings-manage-languages-page',
@@ skipping 33 matching lines @@
   /**
    * Handler for removing a language.
    * @param {!{model: !{item: !LanguageInfo}}} e
    * @private
    */
   onRemoveLanguageTap_: function(e) {
     this.languageHelper_.disableLanguage(e.model.item.language.code);
   },
 
   /**
-   * Handler for adding a language.
-   * @param {!{model: {item: !chrome.languageSettingsPrivate.Language}}} e
+   * Handler for checking or unchecking a language item.
+   * @param {!{model: !{item: !chrome.languageSettingsPrivate.Language},
+   *           target: !PaperCheckboxElement}} e
    * @private
    */
-  onAddLanguageTap_: function(e) {
-    this.languageHelper_.enableLanguage(e.model.item.code);
+  onLanguageCheckboxChange_: function(e) {
+    var code = e.model.item.code;
+    if (e.target.checked)
+      this.languageHelper_.enableLanguage(code);
+    else
+      this.languageHelper_.disableLanguage(code);
   },
 
   /**
-   * True if a language is not the current or prospective UI language.
+   * True if a language is not the current or prospective UI language, ie,
+   * it could be disabled.
    * @param {string} languageCode
    * @param {string} prospectiveUILanguageCode
    * @return {boolean}
    * @private
    */
   canRemoveLanguage_: function(languageCode, prospectiveUILanguageCode) {
     if (languageCode == navigator.language ||
         languageCode == prospectiveUILanguageCode) {
       return false;
     }
-    assert(this.languages.enabledLanguages.length > 1);
     return true;
   },
 
   /**
    * Updates the available languages that are bound to the iron-list.
    * @private
    */
   enabledLanguagesChanged_: function() {
     if (!this.availableLanguages_) {
       var availableLanguages = [];
@@ skipping 11 matching lines @@
     } else {
       // Update the available languages in place.
       for (var i = 0; i < this.availableLanguages_.length; i++) {
         this.set('availableLanguages_.' + i + '.enabled',
                  this.languageHelper_.isLanguageEnabled(
                       this.availableLanguages_[i].code));
       }
     }
   },
 });