6612752: Incorrect getOpenIcon() instanceof in the DefaultTreeCellRenderer

Reviewed-by: serb, pchelko
diff --git a/jdk/src/share/classes/javax/swing/tree/DefaultTreeCellRenderer.java b/jdk/src/share/classes/javax/swing/tree/DefaultTreeCellRenderer.java
index 3cc8bd2..e24ccd9 100644
--- a/jdk/src/share/classes/javax/swing/tree/DefaultTreeCellRenderer.java
+++ b/jdk/src/share/classes/javax/swing/tree/DefaultTreeCellRenderer.java
@@ -191,7 +191,7 @@
         if (!inited || (getClosedIcon() instanceof UIResource)) {
             setClosedIcon(DefaultLookup.getIcon(this, ui, "Tree.closedIcon"));
         }
-        if (!inited || (getOpenIcon() instanceof UIManager)) {
+        if (!inited || (getOpenIcon() instanceof UIResource)) {
             setOpenIcon(DefaultLookup.getIcon(this, ui, "Tree.openIcon"));
         }
         if (!inited || (getTextSelectionColor() instanceof UIResource)) {