Make hit testing work in layout2.dart

sky/examples/raw/hello_world.dart

Index: sky/examples/raw/hello_world.dart
diff --git a/sky/examples/raw/hello_world.dart b/sky/examples/raw/hello_world.dart
index b27b29da7a032579f07fcea5b7cf70dc430f7c6c..61079b5927d1499bed8cffd54005c272ee6beb60 100644
--- a/sky/examples/raw/hello_world.dart
+++ b/sky/examples/raw/hello_world.dart
@@ -20,13 +20,13 @@ Picture draw(int a, int r, int g, int b) {
 bool handleEvent(Event event) {
   if (event.type == "pointerdown") {
     view.picture = draw(255, 0, 0, 255);
-    view.schedulePaint();
+    view.scheduleFrame();
     return true;
   }
 
   if (event.type == "pointerup") {
     view.picture = draw(255, 0, 255, 0);
-    view.schedulePaint();
+    view.scheduleFrame();
     return true;
   }
 
@@ -36,7 +36,7 @@ bool handleEvent(Event event) {
 void main() {
   print("Hello, world");
   view.picture = draw(255, 0, 255, 0);
-  view.schedulePaint();
+  view.scheduleFrame();
 
   view.setEventCallback(handleEvent);
 }