public Builder clearArmorUpgrade() {
        if (armorUpgradeBuilder_ == null) {
          armorUpgrade_ = org.bwapi.proxy.messages.GameMessages.UpgradeType.getDefaultInstance();
          onChanged();
        } else {
          armorUpgradeBuilder_.clear();
        }
        bitField0_ = (bitField0_ & ~0x00000400);
        return this;
      }