[skif] Be more lenient about merging passes with NN filtering
[skif] Be more lenient about merging passes with NN filtering

With the offset image filter using nearest neighbor sampling, the
situation where you're mixing a NN pass with a "default" bilinear pass
increased in frequency. If the bilinear pass was evaluated with an
integer translation it won't change the subsequent NN filtering from the
next pass, so there's no harm in combining the transform directly.

Bug: skia:9283
Change-Id: I1bc6b31babc24e50acb60f88773bf863dddec942
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/600343
Reviewed-by: Robert Phillips <95e8ac5504948c7bf91b22c16a8dbb7ae7c66bfd@google.com>
Auto-Submit: Michael Ludwig <cb1f3dd24de0f0b611b26bc28bec758a551d9b7d@google.com>
Commit-Queue: Michael Ludwig <cb1f3dd24de0f0b611b26bc28bec758a551d9b7d@google.com>

google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia,google/skia