[skottie] Effects cleanup pass

1) switch 2D properties to new Vec2Value type
2) convert vebose binding code to more concise EffectBinder pattern

TBR=

Change-Id: If0244fea887c350dd3d59ddd50a7be75e058d799
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/276639
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
11 files changed