Translate: cleanup on how to pass api key to the script

chrome/browser/resources/translate.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.
 
 // This code is used in conjunction with the Google Translate Element script.
 // It is executed in an isolated world of a page to translate it from one
 // language to another.
 // It should be included in the page before the Translate Element script.
 
 var cr = {};
 
-cr.googleTranslate = (function(key) {
+/**
+ * An object to provide functions to interact with the Translate library.
+ * @type {object}
+ */
+cr.googleTranslate = (function() {
   /**
    * The Translate Element library's instance.
    * @type {object}
    */
   var lib;
 
   /**
    * A flag representing if the Translate Element library is initialized.
    * @type {boolean}
    */
@@ skipping 229 matching lines @@
     },
 
     /**
      * Entry point called by the Translate Element once it has been injected in
      * the page.
      */
     onTranslateElementLoad: function() {
       loadedTime = performance.now();
       try {
         lib = google.translate.TranslateService({
-          'key': key,
+          // translateApiKey is predefined by translate_script.cc.
+          'key': translateApiKey,
           'useSecureConnection': true
         });
+        translateApiKey = undefined;
       } catch (err) {
         error = true;
+        translateApiKey = undefined;
         return;
       }
       // The TranslateService is not available immediately as it needs to start
       // Flash.  Let's wait until it is ready.
       checkLibReady();
     }
   };
-})/* Calling code '(|key|);' will be appended by TranslateHelper in C++ here. */
+})();