getwalletinfo rpc return incorrect data

hello guys,
When I use `getwalletinfo` rpc to query data, I suspect that *balance* is equal to *unconfirmed_balance* according to the returned data, which may be wrong.
So I lookup the code about `getwalletinfo`, which is as follows in the `getWalletInfo` function body:
```
return {
walletid: wallet.id,
walletversion: 6,
balance: Amount.coin(balance.unconfirmed, true),
unconfirmed_balance: Amount.coin(balance.unconfirmed, true),
txcount: balance.tx,
keypoololdest: 0,
keypoolsize: 0,
unlocked_until: wallet.master.until,
paytxfee: Amount.coin(this.wdb.feeRate, true)
};
```
Is this a bug ?

Start at the getWalletInfo function shown in the issue and trace how balance is populated for the getwalletinfo RPC. Compare the sources used for balance and unconfirmed_balance, then verify the response with a wallet containing confirmed and unconfirmed funds. Done means the fields report their intended values, with a regression test if this RPC has existing coverage.

Written by the indexing model from the issue text.