GitLab

Update interpolation of transform lists to reflect recent changes to the spec (https://drafts.csswg.org/css-transforms/#interpolation-of-transforms).

* If the transform lists are of different lengths, but the transformations are pairwise compatible to the end of the shorter list, extend the shorter list with corresponding identity transforms.
* If the transform lists are incompatible, perform pairwise transforms for compatible entities at the start of the list and fallback to matrix interpolation for the remaining transformations.
* Fix discrete fallback.

Bug: 860391, 267348, 918643

Change-Id: I8b2d770e354f3d77dad00e088a2eafe6c1ad655a
Reviewed-on: https://chromium-review.googlesource.com/c/1372025
Commit-Queue: Kevin Ellis <kevers@chromium.org>
Reviewed-by: Ian Vollick <vollick@chromium.org>
Reviewed-by: Stephen McGruer <smcgruer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619661}