modules/graphics/src/main/java/javafx/scene/layout/Pane.java

*** 23,32 ****
--- 23,33 ----
   * questions.
   */
  
  package javafx.scene.layout;
  
+ import com.sun.javafx.scene.layout.PaneHelper;
  import javafx.beans.DefaultProperty;
  import javafx.collections.ObservableList;
  import javafx.scene.Node;
  
  /**
*** 93,102 ****
--- 94,107 ----
   *
   * @since JavaFX 2.0
   */
  @DefaultProperty("children")
  public class Pane extends Region {
+     static {
+         PaneHelper.setPaneAccessor(new PaneHelper.PaneAccessor() {
+         });
+     }
  
      static void setConstraint(Node node, Object key, Object value) {
          if (value == null) {
              node.getProperties().remove(key);
          } else {
*** 115,124 ****
--- 120,133 ----
              }
          }
          return null;
      }
  
+     {
+         // To initialize the class helper at the begining each constructor of this class
+         PaneHelper.initHelper(this);
+     }
      /**
       * Creates a Pane layout.
       */
      public Pane() {
          super();