Implementation of the PortletRequestDispatcher interface.
The portlet request dispatcher is used to dispatch RenderRequest and
RenderResponse to a URI. Note that ActionRequest and ActionResponse
can never be dispatched.
Creates an instance. This constructor should be called to construct a
portlet request dispatcher.
Parameters: requestDispatcher - the servlet request dispatcher. Parameters: queryString - the included query string. See Also:javax.portlet.PortletContext.getRequestDispatcher(String)