[gold] update baseliner and frontend to use new expectation store
[gold] update baseliner and frontend to use new expectation store

Bug: skia:10008
Change-Id: I9c494c26fccbe9cbe327f5c9784ea06c502ff490
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/278786
Reviewed-by: Kevin Lubick <7cdab2cfab351f23814786ba39716e90eed69047@google.com>

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