Scale9Sprite does not work with polygon textures?

Hi, The only place where RenderMode::SLICE9 could be set is - setCenterRectNormalized method :

_renderMode = RenderMode::SLICE9;

But it does not work with Polygon sprites :

void Sprite::setCenterRectNormalized(const cocos2d::Rect &rectTopLeft)
{
if (_renderMode != RenderMode::QUAD && _renderMode != RenderMode::SLICE9) {
CCLOGWARN(“Warning: Sprite::setCenterRectNormalized() only works with QUAD and SLICE9 render modes”);
return;
}

Is this correct that it is not possible to create Scale9Sprite from Polygon texture?

I got the same problem, how can I fix it? Is there a way to use Scale9Sprite with polygon sprite sheet?