Coarse workflow:
* Construction
1) build a Json tree
2) collect asset IDs (for preComp/image layer resolution)
3) "attach" pass
- traverse the Json tree
- build an SkSG dom, one fragment at a time
- attach "animator" objects to the dom, for each animated prop
4) done, we can throw away the Json tree
* For each animation tick
1) iterate over active animators and poke their respective dom nodes/attributes
2) revalidate the SkSG dom
3) draw the SkSG dom
Note: post construction, things are super-simple - we just poke SkSG DOM attributes
with interpolated values, and everything else is handled by SkSG (invalidation,
revalidation, render).
Change-Id: I96a02be7eb4fb4cb3831f59bf2b3908ea190c0dd
Reviewed-on: https://skia-review.googlesource.com/89420
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>