private GTreeNode swingSetModelRootNode(GTreeNode rootNode) {
		GTreeNode oldNode = model.getModelRoot();
		model.privateSwingSetRootNode(rootNode);
		return oldNode;
	}
Sets the root node for this tree.
<P>
NOTE: if this method is not called from the Swing thread, then the root node will be set
later on the Swing thread. That is, this method will return before the work has been done.

@param rootNode The node to set as the new root.
Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/GTree.java