public Builder setCarrier(
          org.bwapi.proxy.messages.GameMessages.UnitId.Builder builderForValue) {
        if (carrierBuilder_ == null) {
          carrier_ = builderForValue.build();
          onChanged();
        } else {
          carrierBuilder_.setMessage(builderForValue.build());
        }
        bitField1_ |= 0x00400000;
        return this;
      }