Error in JSBin Remove property on hide

There is a bug in this JS Bin;
http://jsbin.com/sufate/edit?js,output

An infinite recursion error is caused by line 18.

This is the function:

```
function removeOnHideTransformer(fields) {
return fields.map(function(field) {
field.data = field.data || {};
if (field.key && !field.noFormControl && field.hideExpression && !field.data.dontRemoveOnHidden) {
addFieldRemoveOnHideWatcher(field);
} else if (field.fieldGroup) {
field.fieldGroup = removeOnHideTransformer(fields);
}
return field;
});
}
```

This code

```
else if (field.fieldGroup) {
field.fieldGroup = removeOnHideTransformer(fields);
}
```

Should be

```
else if (field.fieldGroup) {
field.fieldGroup = removeOnHideTransformer(field.fieldGroup);
}
```