Rename "BorderSide.None" to "BorderSide.none", since it's a constant, and change the sky.Size.infin…

sky/sdk/lib/framework/rendering/stack.dart

Index: sky/sdk/lib/framework/rendering/stack.dart
diff --git a/sky/sdk/lib/framework/rendering/stack.dart b/sky/sdk/lib/framework/rendering/stack.dart
index 44e1a7f59ffeae58fc41514d29bfaf27aba68490..80f7bec7b83ebebcfd0e7ea306368e7ba9b31c8d 100644
--- a/sky/sdk/lib/framework/rendering/stack.dart
+++ b/sky/sdk/lib/framework/rendering/stack.dart
@@ -23,11 +23,11 @@ class RenderStack extends RenderBox with ContainerRenderObjectMixin<RenderBox, S
   }
 
   sky.Size getIntrinsicDimensions(BoxConstraints constraints) {
-    return constraints.constrain(new sky.Size.infinite());
+    return constraints.constrain(sky.Size.infinite);
   }
 
   void performLayout() {
-    size = constraints.constrain(new sky.Size.infinite());
+    size = constraints.constrain(sky.Size.infinite);
     assert(size.width < double.INFINITY);
     assert(size.height < double.INFINITY);
     BoxConstraints innerConstraints = new BoxConstraints.loose(size);