travis run: https://travis-ci.org/bitcoin/bitcoin/jobs/406813397

```
rpc_psbt.py failed, Duration: 4 s
stdout:
2018-07-22T13:28:57.765000Z TestFramework (INFO): Initializing test directory /tmp/bitcoin_test_runner_20180722_132530/rpc_psbt_49
2018-07-22T13:29:00.531000Z TestFramework (ERROR): Assertion failed
Traceback (most recent call last):
  File "/home/travis/build/bitcoin/bitcoin/build/bitcoin-x86_64-unknown-linux-gnu/test/functional/test_framework/test_framework.py", line 160, in main
    self.run_test()
  File "/home/travis/build/bitcoin/bitcoin/build/bitcoin-x86_64-unknown-linux-gnu/test/functional/rpc_psbt.py", line 101, in run_test
    assert_raises_rpc_error(-22, "TX decode failed", self.nodes[0].converttopsbt, signedtx['hex'])
  File "/home/travis/build/bitcoin/bitcoin/build/bitcoin-x86_64-unknown-linux-gnu/test/functional/test_framework/util.py", line 105, in assert_raises_rpc_error
    assert try_rpc(code, message, fun, *args, **kwds), "No exception raised"
AssertionError: No exception raised
"\"address\"    (string) The address\n"
                },
                RPCExamples{
                    HelpExampleCli("getrawchangeaddress", "")
            + HelpExampleRpc("getrawchangeaddress", "")
                },
            }.ToString());
    LOCK(pwallet->cs_wallet);
    if (!pwallet->CanGetAddresses(true)) {
        throw JSONRPCError(RPC_WALLET_ERROR, "Error: This wallet has no available keys");
    }
    if (!pwallet->IsLocked()) {
        pwallet->TopUpKeyPool();
    }
    OutputType output_type = pwallet->m_default_change_type != OutputType::CHANGE_AUTO ? pwallet->m_default_change_type : pwallet->m_default_address_type;
    if (!request.params[0].isNull()) {
        if (!ParseOutputType(request.params[0].get_str(), output_type)) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, strprintf("Unknown address type '%s'", request.params[0].get_str()));
        }
    }
    CReserveKey reservekey(pwallet);
    CPubKey vchPubKey;
    if (!reservekey.GetReservedKey(vchPubKey, true))
        throw JSONRPCError(RPC_WALLET_KEYPOOL_RAN_OUT, "Error: Keypool ran out, please call keypoolrefill first");
    reservekey.KeepKey();
    pwallet->LearnRelatedScripts(vchPubKey, output_type);
    CTxDestination dest = GetDestinationForKey(vchPubKey, output_type);
    return EncodeDestination(dest);
}
static UniValue setlabel(const JSONRPCRequest& request)