Instead of applying a transform for every RenderObject, pass down an Offset for where to paint.

sky/sdk/lib/example/widgets/spinning_mixed.dart

Index: sky/sdk/lib/example/widgets/spinning_mixed.dart
diff --git a/sky/sdk/lib/example/widgets/spinning_mixed.dart b/sky/sdk/lib/example/widgets/spinning_mixed.dart
index ffcac6f4b8966c8a417dcd35f1c768e8a74b84c7..9d5bdd0950ad8ef0f2e6b845b2bd56b8c7232686 100644
--- a/sky/sdk/lib/example/widgets/spinning_mixed.dart
+++ b/sky/sdk/lib/example/widgets/spinning_mixed.dart
@@ -14,7 +14,6 @@ import 'package:sky/widgets/widget.dart';
 import 'package:vector_math/vector_math.dart';
 
 import '../lib/solid_color_box.dart';
-import '../../tests/resources/display_list.dart';
 
 // Solid colour, RenderObject version
 void addFlexChildSolidColor(RenderFlex parent, sky.Color backgroundColor, { int flex: 0 }) {
@@ -61,8 +60,6 @@ Widget builder() {
 double timeBase;
 RenderTransform transformBox;
 
-final TestRenderView tester = new TestRenderView();
-
 void rotate(double timeStamp) {
   if (timeBase == null)
     timeBase = timeStamp;
@@ -93,7 +90,7 @@ void main() {
   addFlexChildSolidColor(flexRoot, const sky.Color(0xFF0000FF), flex: 1);
 
   transformBox = new RenderTransform(child: flexRoot, transform: new Matrix4.identity());
-  RenderPadding root = new RenderPadding(padding: new EdgeDims.all(20.0), child: transformBox);
+  RenderPadding root = new RenderPadding(padding: new EdgeDims.all(80.0), child: transformBox);
 
   SkyBinding.instance.root = root;
   addPersistentFrameCallback(rotate);