Fix build after hixie's rename

sky/examples/game/lib/sprite_box.dart

 part of sprites;
 
 enum SpriteBoxTransformMode {
   nativePoints,
   letterbox,
   stretch,
   scaleToFit,
   fixedWidth,
   fixedHeight,
 }
@@ skipping 31 matching lines @@
   }
 
   void handleEvent(Event event) {
     switch (event.type) {
       case 'pointerdown':
         print("pointerdown");
         break;
     }
   }
 
-  void paint(RenderNodeDisplayList canvas) {
+  void paint(RenderObjectDisplayList canvas) {
     // Move to correct coordinate space before drawing
     double scaleX = 1.0;
     double scaleY = 1.0;
     double offsetX = 0.0;
     double offsetY = 0.0;
 
     switch(transformMode) {
       case SpriteBoxTransformMode.stretch:
         scaleX = size.width/_systemWidth;
         scaleY = size.height/_systemHeight;
@@ skipping 67 matching lines @@
     // Count the number of frames we've been running
     _numFrames += 1;
 
     // Print frame rate
     if (_numFrames % 60 == 0) print("delta: ${delta} fps: ${1.0/delta}");
 
     _rootNode.update(delta);
     _scheduleTick();
   }
 }