code: private void unExposeVariables() {
          if (deferredExpression == null) {
              // "nested" variables are now simply removed
              if (itemId != null) {
                  pageContext.removeAttribute(itemId, PageContext.PAGE_SCOPE);
              }
          } else {
              //we're deferred ... remove variable mapping
              ELContext myELContext = pageContext.getELContext();
              VariableMapper vm = myELContext.getVariableMapper();
              vm.setVariable(itemId, null);
          }
          if (statusId != null) {
              pageContext.removeAttribute(statusId, PageContext.PAGE_SCOPE);
          }
      }
docs: Removes page attributes that we have exposed and, if applicable,
  restores them to their prior values (and scopes).