Add SafetyNetLogging and use in SkPngCodec

Bug: b/117838472
Change-Id: I463f8b2c11c07098e9ec24448f66fcafcf6cd76b
Reviewed-on: https://skia-review.googlesource.com/c/170354
Reviewed-by: Derek Sollenberger <djsollen@google.com>
Reviewed-by: Stan Iliev <stani@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
3 files changed