EME: Fix the CDM File IO test when run using unprefixed EME.

media/test/data/eme_player_js/utils.js

 // Copyright 2014 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.
 
 // Utils provide logging functions and other JS functions commonly used by the
 // app and media players.
 var Utils = new function() {
   this.titleChanged = false;
 };
 
@@ skipping 157 matching lines @@
   for (var i = 0; i < uintArray.length; i++) {
     var hex = uintArray[i].toString(16);
     if (hex.length == 1)
       hex = '0' + hex;
     hex_str += hex;
   }
   return hex_str;
 };
 
 Utils.hasPrefix = function(msg, prefix) {
-  var message = String.fromCharCode.apply(null, msg);
+  var message = String.fromCharCode.apply(null, Utils.convertToUint8Array(msg));

[ddorwin, 2016/02/20 00:09:10]

Since there is no way to assert that a Uint8Array was passed in, always do the
conversion.

   return message.substring(0, prefix.length) == prefix;
 };
 
 Utils.installTitleEventHandler = function(element, event) {
   element.addEventListener(event, function(e) {
     Utils.setResultInTitle(e.type);
   }, false);
 };
 
 Utils.isRenewalMessage = function(message) {
   if (message.messageType != 'license-renewal')
     return false;
 
   if (!Utils.isRenewalMessagePrefixed(message.message)) {
     Utils.failTest('license-renewal message doesn\'t contain expected header',
                    PREFIXED_EME_RENEWAL_MISSING_HEADER);
   }
   return true;
 };
 
 // For the prefixed API renewal messages are determined by looking at the
 // message and finding a known string.
 Utils.isRenewalMessagePrefixed = function(msg) {
-  return Utils.hasPrefix(Utils.convertToUint8Array(msg),
-                         PREFIXED_EME_RENEWAL_MESSAGE_HEADER);
+  return Utils.hasPrefix(msg, PREFIXED_EME_RENEWAL_MESSAGE_HEADER);
 };
 
 Utils.resetTitleChange = function() {
   this.titleChanged = false;
   document.title = '';
 };
 
 Utils.sendRequest = function(
     requestType, responseType, message, serverURL, onResponseCallbackFn,
     forceInvalidResponse) {
@@ skipping 62 matching lines @@
   var time = Utils.getCurrentTimeString();
   // Log to document.
   Utils.documentLog(arguments[0], time);
   // Log to JS console.
   var logString = time + ' - ';
   for (var i = 0; i < arguments.length; i++) {
     logString += ' ' + arguments[i];
   }
   console.log(logString);
 };