SkQP:  allow small errors in a small number of pixels

Bug: 80423218

Change-Id: Ied9cb7c72cddb19430b1475bd436bbc8c3ebd3fd
Reviewed-on: https://skia-review.googlesource.com/130541
Reviewed-by: Derek Sollenberger <djsollen@google.com>
3 files changed