Remove expectations / -r from DM entirely.

It's getting tricky to coordinate changes to output for bots with -r,
and -r is not widely used.  The suggested alternative is to run skdiff.

BUG=skia:
R=jcgregorio@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/553583004
16 files changed