MD Settings: Languages; limit platform specific code to the respective platform.

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' handles Chrome's language and input
  * method settings. The 'languages' property, which reflects the current
  * language settings, must not be changed directly. Instead, changes to
  * language settings should be made using the LanguageHelper APIs provided by
  * this class via languageHelper.
@@ skipping 186 matching lines @@
           }.bind(this)));
     }
 
     Promise.all(promises).then(function(results) {
       if (!this.isConnected) {
         // Return early if this element was detached from the DOM before this
         // async callback executes (can happen during testing).
         return;
       }
 
+      // TODO(dpapad): Cleanup this code. It uses results[3] and results[4]
+      // which only exist for ChromeOS.
       this.createModel_(results[1], results[2], results[3], results[4]);
       this.resolver_.resolve();
     }.bind(this));
 
     if (cr.isChromeOS) {
       this.boundOnInputMethodChanged_ = this.onInputMethodChanged_.bind(this);
       this.inputMethodPrivate.onChanged.addListener(
           assert(this.boundOnInputMethodChanged_));
     }
   },
@@ skipping 259 matching lines @@
 
   // LanguageHelper implementation.
   // TODO(michaelpg): replace duplicate docs with @override once b/24294625
   // is fixed.
 
   /** @return {!Promise} */
   whenReady: function() {
     return this.resolver_.promise;
   },
 
+// <if expr="chromeos or is_win">
   /**
    * Sets the prospective UI language to the chosen language. This won't affect
    * the actual UI language until a restart.
    * @param {string} languageCode
    */
   setProspectiveUILanguage: function(languageCode) {
-    assert(cr.isChromeOS || cr.isWindows);
     chrome.send('setProspectiveUILanguage', [languageCode]);
   },
 
   /**
    * True if the prospective UI language was changed from its starting value.
    * @return {boolean}
    */
   requiresRestart: function() {
     return this.originalProspectiveUILanguage_ !=
         this.languages.prospectiveUILanguage;
   },
+// </if>
 
   /**
    * @param {string} languageCode
    * @return {boolean} True if the language is enabled.
    */
   isLanguageEnabled: function(languageCode) {
     return this.enabledLanguageSet_.has(languageCode);
   },
 
   /**
@@ skipping 205 matching lines @@
   },
 
   /**
    * @param {string} languageCode
    * @return {!chrome.languageSettingsPrivate.Language|undefined}
    */
   getLanguage: function(languageCode) {
     return this.supportedLanguageMap_.get(languageCode);
   },
 
-  /**
-   * @param {string} id
-   * @return {!chrome.languageSettingsPrivate.InputMethod|undefined}
-   */
-  getInputMethod: function(id) {
-    assert(cr.isChromeOS);
-    return this.supportedInputMethodMap_.get(id);
-  },
-
+// <if expr="chromeos">
   /** @param {string} id */
   addInputMethod: function(id) {
-    assert(cr.isChromeOS);
     if (!this.supportedInputMethodMap_.has(id))
       return;
     this.languageSettingsPrivate.addInputMethod(id);
   },
 
   /** @param {string} id */
   removeInputMethod: function(id) {
-    assert(cr.isChromeOS);
     if (!this.supportedInputMethodMap_.has(id))
       return;
     this.languageSettingsPrivate.removeInputMethod(id);
   },
 
   /** @param {string} id */
   setCurrentInputMethod: function(id) {
-    assert(cr.isChromeOS);
     this.inputMethodPrivate.setCurrentInputMethod(id);
   },
 
   /**
    * @param {string} languageCode
    * @return {!Array<!chrome.languageSettingsPrivate.InputMethod>}
    */
   getInputMethodsForLanguage: function(languageCode) {
     return this.languageInputMethods_.get(languageCode) || [];
   },
 
   /**
    * @param {!chrome.languageSettingsPrivate.InputMethod} inputMethod
    * @return {boolean}
    */
   isComponentIme: function(inputMethod) {
-    assert(cr.isChromeOS);
     return inputMethod.id.startsWith('_comp_');
   },
 
   /** @param {string} id Input method ID. */
   openInputMethodOptions: function(id) {
-    assert(cr.isChromeOS);
     this.inputMethodPrivate.openOptionsPage(id);
   },
 
   /** @param {string} id New current input method ID. */
   onInputMethodChanged_: function(id) {
-    assert(cr.isChromeOS);
     this.set('languages.inputMethods.currentId', id);
   },
 
   /** @param {string} id Added input method ID. */
   onInputMethodAdded_: function(id) {
-    assert(cr.isChromeOS);
     this.updateEnabledInputMethods_();
   },
 
   /** @param {string} id Removed input method ID. */
   onInputMethodRemoved_: function(id) {
-    assert(cr.isChromeOS);
     this.updateEnabledInputMethods_();
   },
+// </if>
 });
 })();