Update gold aggregators to use new struct

See https://skia-review.googlesource.com/c/buildbot/+/244259

Change-Id: I761aee95e380f56cf9f49be7c4399b231f7f1f43
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/244887
Reviewed-by: Ben Wagner aka dogben <benjaminwagner@google.com>
2 files changed