[Scroll Unif.] Filter compositor transform nodes

Scroll Unification causes transform nodes to be created for all
scrollers, even unpainted ones. This can cause a violation of a DCHECK
in compositor_animations.cc which ensures that a given animation either
has all property nodes on the compositor or none at all.

This patch is to prototype solution given by
https://bugs.chromium.org/p/chromium/issues/detail?id=1385575#c18
in which we avoid creating property (transform) nodes for layers which
are not painted.

Bug: 1385575
Change-Id: I3eaf7806d1c3019685e58a82f8be97ffc4aab503
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4117703
Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: David Awogbemila <awogbemila@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1122033}