Bytes getCallResultStackItem(final MessageFrame childFrame) {
    if (childFrame.getState() == State.COMPLETED_SUCCESS) {
      return LEGACY_SUCCESS_STACK_ITEM;
    } else {
      return LEGACY_FAILURE_STACK_ITEM;
    }
  }
Complete.

@param frame the frame
@param childFrame the child frame
evm/src/main/java/org/hyperledger/besu/evm/operation/AbstractCallOperation.java