Fix undefined GrIORef test method on Chrome win bot

Change-Id: Ifc3d7e285a4b1a0b370ec79963127490bd7b1a84
Reviewed-on: https://skia-review.googlesource.com/6896
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed