Maybe it isn't best solution but it works for me now. I'm duplicating shape geometry from feature and creating new polygon in place.
var shape = [];
for (var i = 0; i < map.data.getFeatureById(ID).getGeometry().getLength(); i++) {
var shapeData = map.data.getFeatureById(ID).getGeometry().getAt(i).getArray();
shape.push(shapeData);
}
nowEditingShape = new google.maps.Polygon({
paths: shape,
strokeColor: '#FF0000',
strokeOpacity: 0.8,
strokeWeight: 2,
fillColor: '#FF0000',
fillOpacity: 0.35,
editable: true
});
map.data.remove(map.data.getFeatureById(ID));
nowEditingShape.setMap(map);