Remove RenderSizedBox.

sky/tests/raw/render_box.dart

Index: sky/tests/raw/render_box.dart
diff --git a/sky/tests/raw/render_box.dart b/sky/tests/raw/render_box.dart
index b94b466c89ee028b2ed118eefbb02f67fb4d8973..e01469248cab8643e04599d01f10bd5b31cd700b 100644
--- a/sky/tests/raw/render_box.dart
+++ b/sky/tests/raw/render_box.dart
@@ -15,10 +15,8 @@ void main() {
   initUnit();
 
   test("should size to render view", () {
-    RenderSizedBox root = new RenderSizedBox(
-      child: new RenderDecoratedBox(
-        decoration: new BoxDecoration(backgroundColor: const sky.Color(0xFF00FF00))
-      )
+    RenderBox root = new RenderDecoratedBox(
+      decoration: new BoxDecoration(backgroundColor: const sky.Color(0xFF00FF00))
     );
     new TestRenderView(root);
     expect(root.size.width, equals(sky.view.width));