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

sky/examples/raw/circle.sky

Index: sky/examples/raw/circle.sky
diff --git a/sky/examples/raw/circle.sky b/sky/examples/raw/circle.sky
index 224e2d9255965ff22c81bd6da50f42c5646c970f..c5818c6aec6aacddd9e4c55c3feeaedba4d9bca5 100644
--- a/sky/examples/raw/circle.sky
+++ b/sky/examples/raw/circle.sky
@@ -14,7 +14,7 @@ void main() {
   var element = document.getElementById('canvas');
   element.requestPaint((PaintingContext context) {
     Paint paint = new Paint();
-    paint.setARGB(128, 0, 255, 0);
+    paint.color = Color.fromARGB(128, 0, 255, 0);
     double radius = math.min(context.width, context.height) / 2.0;
     context.drawCircle(context.width / 2.0, context.height / 2.0, radius, paint);
     context.commit();