Delete SkMakeImageFromPixelRef

There are no callers.

BUG=skia:

Change-Id: Ie743fc61cc0a0ca755d4e3fdab8a5985fa35fbd3
Reviewed-on: https://skia-review.googlesource.com/6598
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
2 files changed