[sksg] Fix setVisible() invalidation

Changes in visibility should generate damage.

TBR=
Change-Id: Ide7b660719b86bc9843d3dcfebeb6e39076879fb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/229279
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
2 files changed