message: Properly track interface roots in AnonymousClassMerging
  Summary: Make the roots metrics more consistent between `AnonymousClassMerging` and `IntraDexClassMerging`
diff: @@ -224,12 +224,13 @@ void discover_mergeable_anonymous_classes(
  // java.lang.Object.
  continue;
  }
  - mgr->incr_metric("cls_" + show(parent), pair.second.size());
  if (is_interface(type_class(parent))) {
  auto first_mergeable = type_class(pair.second[0]);
  merging_spec->roots.insert(first_mergeable->get_super_class());
  + mgr->incr_metric("intf_" + show(parent), pair.second.size());
  } else {
  merging_spec->roots.insert(parent);
  + mgr->incr_metric("cls_" + show(parent), pair.second.size());
  }
  merging_spec->merging_targets.insert(pair.second.begin(),
  pair.second.end());
  