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

sky/sdk/lib/widgets/scaffold.dart

Index: sky/sdk/lib/widgets/scaffold.dart
diff --git a/sky/sdk/lib/widgets/scaffold.dart b/sky/sdk/lib/widgets/scaffold.dart
index 8390a20779535cda004cf7aef6f4ee8cc939e62b..39ac7a306841f535eb03622a193f0be1a778d453 100644
--- a/sky/sdk/lib/widgets/scaffold.dart
+++ b/sky/sdk/lib/widgets/scaffold.dart
@@ -126,12 +126,12 @@ class RenderScaffold extends RenderBox {
     }
   }
 
-  void paint(RenderCanvas canvas) {
+  void paint(RenderCanvas canvas, Offset offset) {
     for (ScaffoldSlots slot in [ScaffoldSlots.body, ScaffoldSlots.statusBar, ScaffoldSlots.toolbar, ScaffoldSlots.floatingActionButton, ScaffoldSlots.drawer]) {
       RenderBox box = _slots[slot];
       if (box != null) {
         assert(box.parentData is BoxParentData);
-        canvas.paintChild(box, box.parentData.position);
+        canvas.paintChild(box, box.parentData.position + offset);
       }
     }
   }