FULL PRODUCT VERSION :
java version "1.8.0_92"
Java(TM) SE Runtime Environment (build 1.8.0_92-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.92-b14, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
To reproduce just launch class below and collapse root tree - you will see that child treeItem graphics are still visible.



REGRESSION.  Last worked in version 8u91

ADDITIONAL REGRESSION INFORMATION: 
java version "1.8.0_91"
Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
When you collapse root tree - you should not see graphics that left from child treeItems
ACTUAL -
When you collapse root tree - you can see graphics that left from child treeItems

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.Collection;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyStringWrapper;
import javafx.scene.Scene;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeTableColumn;
import javafx.scene.control.TreeTableView;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;

public class Test extends Application {

	public void start(Stage pStage) {
		pStage.setTitle("Test");

		// create tree items
		final TreeItem<String> root = new TreeItem<>("Root Node");
		root.setExpanded(true);
		
		final Collection<TreeItem<String>> children = IntStream.rangeClosed(1, 5)
				.mapToObj(pIdx ->new TreeItem<>("Child Node " + pIdx, new Rectangle(10, 10)))
				.collect(Collectors.toList());

		root.getChildren().addAll(children);
		
		// create  TreeTableView
		final TreeTableView<String> treeTableView = new TreeTableView<>(root);
		final TreeTableColumn<String,String> column = new TreeTableColumn<>("Column");
		column.setCellValueFactory(
				pTreeItem -> new ReadOnlyStringWrapper(pTreeItem.getValue().getValue()));
		treeTableView.getColumns().add(column);
		
		pStage.setScene(new Scene(treeTableView, 300, 450));
		pStage.show();
	}

	public static void main(String[] pArgs) {
		launch(pArgs);
	}
} 
---------- END SOURCE ----------