ScraperError = function(message) {
	/**
	 * Error message.
	 *
	 * @type {!string}
	 * @public
	 */
	this.message = message;
	/**
	 * This type.
	 *
	 * @type {!string}
	 * @public
	 */
	this.name = 'ScraperError';
	/**
	 * Stack message.
	 *
	 * @type {!string}
	 * @public
	 */
	this.stack = (new Error()).stack;
}
A scraper error, to refer error occurred in the scope of this
  package. For more information about the error use it's message
  property.

@param   {!string} message Error message.
@extends {Error}