attachRootRenderObject method
Attach the root render object used as the pipeline frame root.
Implementation
void attachRootRenderObject(RenderObjectWithSingleChild root) {
final existing = _rootRenderObject;
if (existing != null && !identical(existing, root)) {
throw StateError('BuildOwner already has a root render object');
}
_rootRenderObject = root;
(root as RenderObject).attach(pipelineOwner);
_pointerRouter.root = root;
}