@Override
	void close() {
		child1.close();
		child2.close();
	}
Constructs a new SplitNode from the XML JDOM element
@param elem the XML JDOM element containing the configuration information.
@param mgr the DockingWindowsManager for this node.
@param parent the parent node for this node.
@param restoredPlaceholders the list into which any restored placeholders will be placed
Ghidra/Framework/Docking/src/main/java/docking/SplitNode.java