Remove flexible runtime effects entirely

All internal usage has migrated to MakeFor..., this removes the old
program kind, and updates some tests.

Bug: skia:11813
Change-Id: I56733b071270e1ae3fab5d851e23acf6c02e3361
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/402536
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
47 files changed