[skottie] Motion tile effect

Implement support for AE's Motion Tile effect [1].

This is the first effect which needs layer size information, so the CL includes
related plumbing.

Limitations: no phase support at this point.

[1] https://helpx.adobe.com/after-effects/using/stylize-effects.html#motion_tile_effect

Change-Id: I023bf8a9d3e3d2a48458fa94218f143e6aac4c9f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/221244
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
12 files changed