[skottie] Fix handling of time-reversed precomp layers

With time-reverse enabled

 - inPoint/outPoint are reversed
 - time stretch is negative

Bug: skia:9958
Change-Id: I5c1197251608aad4b0417cde6ca2600b1b2822fc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/273808
Commit-Queue: Avinash Parchuri <aparchur@google.com>
Reviewed-by: Avinash Parchuri <aparchur@google.com>
2 files changed