@Nonnull
	private List<TreeContent> buildTreeRoots(@Nonnull Tree<String, ClassPathNode> tree) {
		if (tree.isBranch()) {
			ObservableList<TreeContent> list = FXCollections.observableArrayList();
			for (Tree<String, ClassPathNode> subtree : tree.values())
				list.addAll(buildTreeRoots(subtree));
			return Collections.singletonList(new SimpleHierarchicalTreeContent(new SimpleListProperty<>(list)));
		} else {
			ClassPathNode value = tree.getValue();
			if (value == null)
				return Collections.emptyList();
			return Collections.singletonList(toContent(value));
		}
	}
Pane to display the current mapping progress of classes in the workspace.
Classes change color to indicate if they are mapped or not, and how fully mapped their declared members are.

@author Matt Coley
@see MappingProgressWindow
recaf-ui/src/main/java/software/coley/recaf/ui/pane/MappingProgressPane.java