Use an enum for Dart bindings for Skia Paint style

sky/engine/core/painting/Paint.idl

Index: sky/engine/core/painting/Paint.idl
diff --git a/sky/engine/core/painting/Paint.idl b/sky/engine/core/painting/Paint.idl
index f86cc75451581f64776efdb4042583f2864b2f7b..ae8f662c748ceb3040a0b63b960637a2bd87c1d2 100644
--- a/sky/engine/core/painting/Paint.idl
+++ b/sky/engine/core/painting/Paint.idl
@@ -5,13 +5,6 @@
 [
   Constructor(),
 ] interface Paint {
-  // Style
-  const unsigned short FILL_STYLE            = 0;
-  const unsigned short STROKE_STYLE          = 1;
-  const unsigned short STROKE_AND_FILL_STYLE = 2;
-
-  // TODO(jackson): we could wrap this enum like we did for |color|
-  attribute unsigned short style;
   attribute float strokeWidth;
   attribute boolean isAntiAlias;
   attribute Color color;
@@ -21,5 +14,6 @@
   void setDrawLooper(DrawLooper looper);
   void setColorFilter(ColorFilter filter);
   void setMaskFilter(MaskFilter filter);
+  void setStyle(PaintingStyle style);
   void setTransferMode(TransferMode transferMode);
 };