Add a GifTest for the Haeberli hack

Bug: skia:8766
Change-Id: I5e6ad0a613a3454bf17fd492f1ab4d7831e59092
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/240736
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
1 file changed