Bug 130492 Provide a method to serialize the report with library information.
Currently, when engine generate the report document file, the document does not contain any library information. That will cause many propblem on server side. Model should provide a method to serialize the report with library information to a stream so that the generated report document can contain all information that the report need.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
listeners.add( obj );
	}
	/**
	 * Removes a listener. The listener is removed from the list of listeners.
	 * If the item is not in the list, then the request is silently ignored.
	 * <p>
	 * Part of: Notification system.
	 * 
	 * @param obj
	 *            the listener to remove
	 */
	public void removeListener( Listener obj )
	{
		if ( listeners == null )
			return;
		int posn = listeners.indexOf( obj );
		if ( posn != -1 )
			listeners.remove( posn );
	}
	/**
	 * Removes all listeners on this element.
	 * <p>
	 * Part of: Notification system.
	 */
	public void clearListeners( )
	{
		if ( listeners != null )
			listeners.clear( );
		listeners = null;
	}