Revert "Consolidate read/write-Pixels testing code"

This reverts commit 0bd4a23ef40d74ef051eb7f457c133d5febc377d.

Reason for revert: What?!?

Original change's description:
> Consolidate read/write-Pixels testing code
> 
> Change-Id: I853f8f747ed0040333473fbc722cabac84e6ac83
> Reviewed-on: https://skia-review.googlesource.com/7560
> Commit-Queue: Robert Phillips <robertphillips@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>
> 

TBR=robertphillips@google.com,brianosman@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I9cb049a4f86350f849d00839a55b55fb07e861b0
Reviewed-on: https://skia-review.googlesource.com/7648
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
6 files changed