Cleaning up and updating mock_chrome.js

chrome/browser/resources/file_manager/js/metadata_provider.js

 // Copyright (c) 2011 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.
 
 /**
  * @param {string} opt_workerPath path to the worker source JS file.
  */
 function MetadataProvider(opt_workerPath) {
   this.cache_ = {};
 
   // Pass all URLs to the metadata reader until we have a correct filter.
   this.urlFilter = /.*/;
 
-  this.dispatcher_ = new Worker(opt_workerPath ||
-      document.location.origin + '/js/metadata_dispatcher.js');
+  if (!opt_workerPath) {
+    var path = document.location.pathname;
+    opt_workerPath = path.substring(0, path.lastIndexOf('/') + 1) +
+        'js/metadata_dispatcher.js';
+  }
+
+  this.dispatcher_ = new Worker(opt_workerPath);
   this.dispatcher_.onmessage = this.onMessage_.bind(this);
   this.dispatcher_.postMessage({verb: 'init'});
   // Initialization is not complete until the Worker sends back the
   // 'initialized' message.  See below.
 }
 
 MetadataProvider.prototype.fetch = function(url, callback) {
   var cacheValue = this.cache_[url];
 
   if (!cacheValue) {
@@ skipping 74 matching lines @@
 };
 
 MetadataProvider.prototype.onError_ = function(url, step, error, metadata) {
   console.warn('metadata: ' + url + ': ' + step + ': ' + error);
   this.onResult_(url, metadata || {});
 };
 
 MetadataProvider.prototype.onLog_ = function(arglist) {
   console.log.apply(console, ['metadata:'].concat(arglist));
 };