Changes check_for_regressions back to reading expectations from git repo; changes expectations location to expectations/bench.
Changes check_for_regressions back to reading expectations from git repo; changes expectations location to expectations/bench.

BUG=skia:2225
NOTRY=true
R=borenet@google.com

Author: bensong@google.com

Review URL: https://codereview.chromium.org/215313004

google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot,Tiger66639/skia-buildbot,Tiger66639/skia-buildbot,google/skia-buildbot