Remove redundant Paint.setARGB in favor of assigning to Paint.color.

sky/examples/raw/draw_picture_into_canvas.sky

Index: sky/examples/raw/draw_picture_into_canvas.sky
diff --git a/sky/examples/raw/draw_picture_into_canvas.sky b/sky/examples/raw/draw_picture_into_canvas.sky
index 95f9ca19926fc98460a5aec85ef6d859a0a38820..6b8024d9ba13b9ca7f471a6a99618dd8aff30c37 100644
--- a/sky/examples/raw/draw_picture_into_canvas.sky
+++ b/sky/examples/raw/draw_picture_into_canvas.sky
@@ -15,7 +15,7 @@ void main() {
   Picture stamp = stampRecorder.endRecording();
 
   PictureRecorder recorder = new PictureRecorder(width, height);
-  Paint paint = new Paint()..setARGB(255, 0, 255, 0);
+  Paint paint = new Paint()..color = Color.fromARGB(255, 0, 255, 0);
   recorder.drawCircle(50.0, 50.0, 50.0, paint);
   recorder.translate(10.0, 10.0);
   recorder.drawPicture(stamp);