void replaceView(ProgramNode node) {
		tree.setViewPaths(new TreePath[] { node.getTreePath() });
	}
Set the action state depending on what the user double-clicked. 

Row = -1: The user clicked the expand/collapse icon.  Just nothing regarding
          selection or the view.
Row = 0+: The user clicked a node (root or fragment); select that node
          for view.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/programtree/ProgramTreePanel.java