[skottie] Fix start-time/stretch-time handling

We currently apply start-time/stretch-time adjustments to the referenced
composition AND to the referencing layer local properties.  That last
part is incorrect: the adjustment should only apply to the referenced

Introduce a specialized composition time mapper to handle t adjustments,
and push the logic down to AttachCompLayer (and out of the generic

Change-Id: I0ddb86232010a8e7cdac6524aef2eea5823e306d
Reviewed-on: https://skia-review.googlesource.com/136166
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
1 file changed