On my Linux Mint 19.1:
```bash
$ umask
0022
```

After the first run of `bitcoin-qt -sysperm=false` the `0700` permissions are expected for both the datadir (`~/.bitcoin`) and the walletdir (`~/.bitcoin/wallets`).

Actually, the directories are created with such access permissions:
```bash
$ stat ~/.bitcoin | grep Uid
Access: (0755/drwxr-xr-x)  Uid: ( 1000/ hebasto)   Gid: ( 1000/ hebasto)
$ stat ~/.bitcoin/wallets | grep Uid
Access: (0755/drwxr-xr-x)  Uid: ( 1000/ hebasto)   Gid: ( 1000/ hebasto)
```

Refs:
- #4286
- #13371
- #13389

NOTE: reading through the initial PR #4286 makes me think it was controversial. Is it a better and simpler way to just get rid of `-sysperm` option? I believe a user who needs this option can easily run `chown` command.
{
    const Binary& decoded = DecodeI2PBase64(dest);
    return DestBinToAddr(decoded);
}
namespace sam {
Session::Session(const fs::path& private_key_file,
                 const CService& control_host,
                 CThreadInterrupt* interrupt)
    : m_private_key_file{private_key_file},
      m_control_host{control_host},
      m_interrupt{interrupt},
      m_control_sock{std::make_unique<Sock>(INVALID_SOCKET)},
      m_transient{false}
{
}
Session::Session(const CService& control_host, CThreadInterrupt* interrupt)