get image from skcodec

Part of the larger work to remove drawImage from canvas (and in general
simplify our apis w.r.t. older patterns like skbitmap).

Change-Id: If208927e1d46256519036c42e68aec3d3c809a82
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/358836
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Mike Reed <reed@google.com>
7 files changed