Extract language settings methods into a LanguageHelper interface

chrome/browser/resources/settings/languages_page/languages_page.js

Index: chrome/browser/resources/settings/languages_page/languages_page.js
diff --git a/chrome/browser/resources/settings/languages_page/languages_page.js b/chrome/browser/resources/settings/languages_page/languages_page.js
index dd43e36703e0354d6c2b86bd6bcfe3b9c0273679..bdf3cdd357173c69e6f63620db037e9f1b98a775 100644
--- a/chrome/browser/resources/settings/languages_page/languages_page.js
+++ b/chrome/browser/resources/settings/languages_page/languages_page.js
@@ -43,6 +43,9 @@ Polymer({
     },
   },
 
+  /** @private {LanguageSettingsHelper} */
+  languageHelper_: settings.LanguageHelper.getInstance(),
+
   /**
    * Handler for clicking a language on the main page, which selects the
    * language as the prospective UI language on Chrome OS and Windows.
@@ -55,7 +58,7 @@ Polymer({
 
     // Set the prospective UI language. This won't take effect until a restart.
     if (e.model.item.language.supportsUI)
-      this.$.languages.setUILanguage(e.model.item.language.code);
+      this.languageHelper_.setUILanguage(e.model.item.language.code);
   },
 
   /**
@@ -63,8 +66,8 @@ Polymer({
    * @param {!{target: Element, model: !{item: !LanguageInfo}}} e
    */
   onSpellCheckChange_: function(e) {
-    this.$.languages.toggleSpellCheck(e.model.item.language.code,
-                                      e.target.checked);
+    this.languageHelper_.toggleSpellCheck(e.model.item.language.code,
+                                         e.target.checked);

[Dan Beam, 2015/11/18 18:06:01]

indent off

[michaelpg, 2015/11/22 00:22:40]

Done.

   },
 
   /** @private */
@@ -110,7 +113,8 @@ Polymer({
    * @private
    */
   isUILanguage_: function(languageCode, prospectiveUILanguage) {
-    return languageCode == this.$.languages.getProspectiveUILanguage();
+    return (cr.isWindows || cr.isChromeOS) &&

[Dan Beam, 2015/11/18 18:06:01]

can you somehow explain why this only happens on Windows/ChromeOS? i.e.

var platformHasSpellchecking

or

var respectsUILanguage

or a comment, or a private method, or...

[michaelpg, 2015/11/22 00:22:40]

Done.

+           languageCode == this.languageHelper_.getProspectiveUILanguage();
   },
 
   /**