public Builder setRaces(
          int index, org.bwapi.proxy.messages.GameMessages.RaceData.Builder builderForValue) {
        if (racesBuilder_ == null) {
          ensureRacesIsMutable();
          races_.set(index, builderForValue.build());
          onChanged();
        } else {
          racesBuilder_.setMessage(index, builderForValue.build());
        }
        return this;
      }