New thin layer of API extension chrome.i18n.detectLanguage

chrome/test/data/extensions/api_test/i18n/test.js

 // Copyright (c) 2012 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.
 
 // i18n api test
 // browser_tests.exe --gtest_filter=ExtensionApiTest.I18N --lib=browser_tests
 
 var testCallback = chrome.test.testCallback;
 var callbackPass = chrome.test.callbackPass;
 
@@ skipping 41 matching lines @@
       chrome.test.log("Creating tab...");
       chrome.tabs.create({
         url: TEST_FILE_URL
       });
       chrome.test.succeed();
     },
     function getUILanguage() {
       chrome.test.assertEq('en-US', chrome.i18n.getUILanguage());
       chrome.test.succeed();
     }
+    /*,

[Takashi Toyoshima, 2015/07/08 03:19:42]

Why this part is commented out? If this does not work for now, I prefer adding
this test when it gets working.

[amalika, 2015/07/08 21:58:03]

Done.

+    function detectLanguage() {
+      chrome.i18n.detectLanguage("hello", callbackPass(function(results) {
+        chrome.test.assertEq(results.length, 2);
+        chrome.test.assertEq(results[0], "en-US");
+        chrome.test.assertEq(results[1], "en");
+      }));
+    }
+    */
   ]);
 });