Support geometry and coord boxes in shape interpolation

Animations for `clip-path` and `offset-path` did not previously
account for their respective `geometry-box` and `coord-box` values.
This resulted in incorrect interpolation when these boxes differed
between keyframes. The CSS specification requires a discrete animation
in such cases.

This change updates the shape interpolation logic to treat the
reference box as a non-interpolable component. The box is now parsed
and stored with the shape data. If the boxes differ between the start
and end values of an animation, the animation will correctly fall
back to discrete interpolation.

Bug: 450326418
Change-Id: I1b6f113b1257f94dcceac6f8b7e716015e39f165
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7032120
Commit-Queue: Daniil Sakhapov <sakhapov@chromium.org>
Reviewed-by: Kevin Ellis <kevers@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1529973}