Add CheckGeneratedFiles recipe check for gpu workarounds

Followup to https://skia-review.googlesource.com/122800

Bug: chromium: 829614
Change-Id: Idde753e0f8943290208625ba5b6332a5fdc07184
Reviewed-on: https://skia-review.googlesource.com/123536
Commit-Queue: Adrienne Walker <enne@chromium.org>
Commit-Queue: Eric Boren <borenet@google.com>
Auto-Submit: Adrienne Walker <enne@chromium.org>
Reviewed-by: Eric Boren <borenet@google.com>
5 files changed