message: Fix get contract sender address
diff: @@ -88,7 +88,8 @@ WalletTx MakeWalletTx(CWallet& wallet, const CWalletTx& wtx)
  if(result.has_create_or_call)
  {
  CTxDestination tx_sender_address;
  - if(ExtractDestination(wallet.mapWallet.at(wtx.tx->vin[0].prevout.hash).tx->vout[wtx.tx->vin[0].prevout.n].scriptPubKey, tx_sender_address)) {
  + if(wtx.tx && wtx.tx->vin.size() > 0 && wallet.mapWallet.find(wtx.tx->vin[0].prevout.hash) != wallet.mapWallet.end() &&
  + ExtractDestination(wallet.mapWallet.at(wtx.tx->vin[0].prevout.hash).tx->vout[wtx.tx->vin[0].prevout.n].scriptPubKey, tx_sender_address)) {
  result.tx_sender_key = GetKeyForDestination(wallet, tx_sender_address);
  }
  