`ScanForWalletTransactions()` has the following comment about its return value:

```
 * Returns null if scan was successful. Otherwise, if a complete rescan was not
 * possible (due to pruning or corruption), returns pointer to the most recent
 * block that could not be scanned.
```

This is not strictly true. If `abortrescan` is called, then `ScanForWalletTransactions()` will return `nullptr`, even though the scan wasn't successful to the tip.

This in turn causes a minor bug in `importmulti`, where the call doesn't return the correct error and warning about potentially not finding transactions if `abortrescan` was called.

I think the correct fix is for `ScanForWalletTransactions()` to inform the caller that the rescan was aborted.
SetMinVersion(FEATURE_WALLETCRYPT, encrypted_batch, true);
        if (!encrypted_batch->TxnCommit()) {
            delete encrypted_batch;
            encrypted_batch = nullptr;
            
            
            assert(false);
        }
        delete encrypted_batch;
        encrypted_batch = nullptr;
        Lock();
        Unlock(strWalletPassphrase);
        
        if (IsHDEnabled()) {
            SetHDSeed(GenerateNewSeed());
        }
        NewKeyPool();
        Lock();
        
        
        database->Rewrite();
        
        
        
        database->ReloadDbEnv();
    }
    NotifyStatusChanged(this);
    return true;
}
DBErrors CWallet::ReorderTransactions()