Empty enums

After Wordpress 4.7 upgrade empty enums appeared into template POST parameters in several enpoints (Page, Post):

e.g.:

    {  
      "name":"template",
      "type":"string",
      "in":"formData",
      "description":"Teematiedosto joka n\u00e4ytt\u00e4\u00e4 kohteen.",
      "enum":[
        ""
      ]
    }