Reland "[skottie] skottie_tool updates"

This reverts commit d424d6a3bd07241565bedb5a62eebf12bf81a87c.

Reason for revert: ready to reland

Original change's description:
> Revert "[skottie] skottie_tool updates"
> 
> This reverts commit 6499e7fb4c6d05afdce3172e3d7ef39018700ae9.
> 
> Reason for revert: G3 roll
> 
> Original change's description:
> > [skottie] skottie_tool updates
> > 
> > 1) plumb a precomp interceptor to support nested animations, following
> >    the same naming pattern as viewer and dm
> > 
> > 2) clear background with white instead of transparent, to match other
> >    tools
> > 
> > TBR=
> > Change-Id: Ic1d1f8c6493a3ca98a9b75f5e2aa2230a46f54d9
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/298139
> > Reviewed-by: Florin Malita <fmalita@chromium.org>
> > Commit-Queue: Florin Malita <fmalita@google.com>
> 
> TBR=fmalita@chromium.org,fmalita@google.com
> 
> Change-Id: Ibd320e9f7f30004e80ff4d2b2012a18703910842
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/298337
> Reviewed-by: Florin Malita <fmalita@google.com>
> Commit-Queue: Florin Malita <fmalita@google.com>

TBR=fmalita@chromium.org,fmalita@google.com

# Not skipping CQ checks because this is a reland.

Change-Id: Id20c88771caf580519e1e92dc293933041522f7a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/298561
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
1 file changed