Add tolerance to ProcessorCloneTest and dump images on failure.

Change-Id: Id36aef0392f03aafe3f90d5d905b2b2f30a67c04
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/234317
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
1 file changed