Split Size into Size and Offset.

sky/sdk/lib/rendering/sky_binding.dart

Index: sky/sdk/lib/rendering/sky_binding.dart
diff --git a/sky/sdk/lib/rendering/sky_binding.dart b/sky/sdk/lib/rendering/sky_binding.dart
index 29408f73120257c8cd0421d027086f50c51a7fe9..ca441273752a9887745bdf6427baba1c60aa9b6a 100644
--- a/sky/sdk/lib/rendering/sky_binding.dart
+++ b/sky/sdk/lib/rendering/sky_binding.dart
@@ -48,7 +48,7 @@ class SkyBinding {
   RenderView get renderView => _renderView;
 
   ViewConstraints _createConstraints() {
-    return new ViewConstraints(width: sky.view.width, height: sky.view.height);
+    return new ViewConstraints(size: new Size(sky.view.width, sky.view.height));
   }
   void _handleMetricsChanged() {
     _renderView.rootConstraints = _createConstraints();