message: [Script] Guard against GetPubKey() failures in Solver()
diff: @@ -93,7 +93,8 @@ bool Solver(const CKeyStore& keystore, const CScript& scriptPubKey, uint256 hash
  else
  {
  CPubKey vch;
  - keystore.GetPubKey(keyID, vch);
  + if (!keystore.GetPubKey(keyID, vch))
  + return error("%s : Unable to get public key from keyID", __func__);
  scriptSigRet << ToByteVector(vch);
  }
  return true;
  @@ -116,7 +117,8 @@ bool Solver(const CKeyStore& keystore, const CScript& scriptPubKey, uint256 hash
  return error("*** %s: failed to sign with the %s key.",
  __func__, fColdStake ? "cold staker" : "owner");
  CPubKey vch;
  - keystore.GetPubKey(keyID, vch);
  + if (!keystore.GetPubKey(keyID, vch))
  + return error("%s : Unable to get public key from keyID", __func__);
  scriptSigRet << (fColdStake ? (int)OP_TRUE : OP_FALSE) << ToByteVector(vch);
  return true;
  }
  