Separate the audio player app from Files.app

ui/file_manager/audio_player/js/audio_player.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.
 
 'use strict';
 
 /**
+ * Overrided metadata worker's path.
+ * @type {string}
+ * @const
+ */
+ContentProvider.WORKER_SCRIPT = '/js/metadata_worker.js';
+
+/**
  * @param {HTMLElement} container Container element.
  * @constructor
  */
 function AudioPlayer(container) {
   this.container_ = container;
   this.volumeManager_ = new VolumeManagerWrapper(
       VolumeManagerWrapper.DriveEnabledStatus.DRIVE_ENABLED);
   this.metadataCache_ = MetadataCache.createFull(this.volumeManager_);
   this.selectedEntry_ = null;
 
@@ skipping 402 matching lines @@
   this.title = (metadata.media && metadata.media.title) ||
       this.getDefaultTitle();
   this.artist = error ||
       (metadata.media && metadata.media.artist) || this.getDefaultArtist();
 };
 
 // Starts loading the audio player.
 window.addEventListener('polymer-ready', function(e) {
   AudioPlayer.load();
 });