fix missing error message for z_importwallet

src/wallet/rpcdump.cpp

@@ -495,6 +495,10 @@ UniValue importwallet_impl(const UniValue& params, bool fHelp, bool fImportZKeys
                   pwalletMain->nTimeFirstKey = nTimeBegin;
              pwalletMain->ScanForWalletTransactions(pindex);
              pwalletMain->MarkDirty();
+
+     if (!fGood)
+         throw JSONRPCError(RPC_WALLET_ERROR, "Error adding some keys to wallet");
+
          return NullUniValue; }
 
          else{