dropChildRenderObject method
Drop child from this element's render object. childElement is null
when the drop happens as part of a re-sync pass rather than an element
removal.
Implementation
void dropChildRenderObject(RenderObject child, Element? childElement) {
final parentRenderObject = _renderObject;
if (parentRenderObject == null) return;
if (child.parent != parentRenderObject) return;
parentRenderObject.dropChild(child);
}