code: protected Map<String, AclType> getSpaceACLs(HttpServletRequest request) {
          String storeId = getStoreId(request);
          String spaceId = getSpaceId(request);
          return getSpaceACLs(storeId, spaceId);
      }
docs: This method returns the ACLs of the requested space, or an empty-map if
  there is an error or for certain 'keyword' spaces, or null if the space
  does not exist.
  
  @param request containing spaceId and storeId
  @return ACLs, empty-map, or null