bench: Add PhoneHub assets to skottie-vs-png decode bench

The skottie-vs-png decode bench is intended to facilitate comparison
between Lottie and PNG, but such a comparison cannot really be made when
the Lottie files are unrelated to the PNG files (Lottie files chosen to
represent a range of vector graphic complexity, versus PNG files chosen
to represent a range of image dimensions). This CL adds PhoneHub assets
in PNG and Lottie, including various Lottie files created using
different optimization strategies (see added code comments for details).

Change-Id: I1a4357ab0af22b9db7b7ce83fd07d48c77db7680
Bug: chromium:1128684
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/442476
Reviewed-by: Avery Musbach <amusbach@google.com>
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
26 files changed