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

sky/sdk/lib/rendering/block.dart

Index: sky/sdk/lib/rendering/block.dart
diff --git a/sky/sdk/lib/rendering/block.dart b/sky/sdk/lib/rendering/block.dart
index e1198688a53a4cdd7d9d79931406dc4edc8c8487..c93188b4c9652c9ae380c55e63301d2f1d4d6e48 100644
--- a/sky/sdk/lib/rendering/block.dart
+++ b/sky/sdk/lib/rendering/block.dart
@@ -102,8 +102,8 @@ class RenderBlock extends RenderBox with ContainerRenderObjectMixin<RenderBox, B
     defaultHitTestChildren(result, position: position);
   }
 
-  void paint(RenderCanvas canvas) {
-    defaultPaint(canvas);
+  void paint(RenderCanvas canvas, Offset offset) {
+    defaultPaint(canvas, offset);
   }
 
 }