DM: read image files without an extra copy

BUG=skia:
R=halcanary@google.com, reed@google.com, bsalomon@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/185263012

git-svn-id: http://skia.googlecode.com/svn/trunk@13669 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed