Stellar SetOptions requires Signer to be present

[tsusanka]

Although SetOptions does not need Signer, it requiers the field to be present. This following transaction fails:

{
  "source": "GDNAQREX5VOHMYZ2QDHDY6A7XR2OYIE67EETL5MFCT6TCGHYA7YHACEW",
  "fee": 100,
  "sequence": "89703140756029442",
  "operations": [
    {
      "type": "setOptions",
      "inflationDest": "GCCD6AJOYZCUAQLX32ZJF2MKFFAUJ53PVCFQI3RHWKL3V47QYE2BNAUT",
    }
  ],
  "memo": {
    "type": 0
  }
}

on error Cannot read property 'type' of undefined. This tx is however correct:

{
  "source": "GDNAQREX5VOHMYZ2QDHDY6A7XR2OYIE67EETL5MFCT6TCGHYA7YHACEW",
  "fee": 100,
  "sequence": "89703140756029442",
  "operations": [
    {
      "type": "setOptions",
      "inflationDest": "GCCD6AJOYZCUAQLX32ZJF2MKFFAUJ53PVCFQI3RHWKL3V47QYE2BNAUT",
      "signer": ""
    }
  ],
  "memo": {
    "type": 0
  }
}