we don't use memoize anymore

Change-Id: I2061b9e1d37c52a7dcf4000f2ffff553bd9f81ba
Reviewed-on: https://gerrit.instructure.com/28709
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: James Williams  <jamesw@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>