[skottie] Convert (most of) SkottieSlide2 to SkSceneGraph

Each Skottie animation is now a transformed sksg node.

TBR=

Change-Id: Ib5c153e8279e1a74a242b0eb193c4463898b09ea
Reviewed-on: https://skia-review.googlesource.com/102201
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
3 files changed