code: public static PageFlowStack get( HttpServletRequest request, boolean createIfNotExist )
      {
          return get( request, InternalUtils.getServletContext( request ), createIfNotExist );
      }
docs: Get the stack of nested page flows for the current user session.  Create and store an empty
  stack if none exists.
  @deprecated Use {@link #get(HttpServletRequest, ServletContext, boolean)} instead.
  
  @param request the current HttpServletRequest
  @return a {@link PageFlowStack} of nested page flows ({@link PageFlowController}s) for the current user session.