protected String getText(Tree tree) {
		String s = treeTextProvider.getText(tree);
		s = Utils.escapeWhitespace(s, false);
		return s;
	}
Get an adaptor for root that indicates how to walk ANTLR trees.
 Override to change the adapter from the default of {@link TreeLayoutAdaptor}
tool/src/org/antlr/v4/gui/TreePostScriptGenerator.java