hide drawlooper from paint

Bug: skia: 4783

Change-Id: I1d0ad1683a2e8345d8ea13db9b69b568ada827dc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/228573
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
24 files changed