| Find the root WebApplicationContext for this portlet application, which is
typically loaded via ContextLoaderListener or ContextLoaderServlet.
Will rethrow an exception that happened on root context startup,
to differentiate between a failed context startup and no context at all.
Parameters: pc - PortletContext to find the web application context for the root WebApplicationContext for this web app, or null if none(typed to ApplicationContext to avoid a Servlet API dependency; can usuallybe casted to WebApplicationContext, but there shouldn't be a need to) See Also: org.springframework.web.context.WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE |