code: public static String normalizeRequestURI(final FacesContext context, final String viewId)
     {
        ExternalContext externalContext = context.getExternalContext();
        return normalizeRequestURI(externalContext.getRequestServletPath(), externalContext.getRequestPathInfo(), viewId);
     }
docs: This method reads all required values from the {@link FacesContext} and
  then delegates the call to
  {@link #normalizeRequestURI(String, String, String)}.
  
  @param context
  The {@link FacesContext}
  @param viewId
  the view id
  @return the URI without additional FacesServlet mappings