code: function() {
      this._readyState = 0;
      this._error = null;
      this._result = null;
      this._progress = null;
      this._localURL = '';
      this._realReader = origFileReader ? new origFileReader() : {};
  }
docs: This class reads the mobile device file system.
  
  For Android:
  The root directory is the root of the file system.
  To read from the SD card, the file name is "sdcard/my_file.txt"
  @constructor