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

sky/sdk/lib/widgets/scaffold.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import '../rendering/box.dart';
 import '../rendering/object.dart';
 import '../theme/view_configuration.dart';
 import 'widget.dart';
 
 enum ScaffoldSlots {
@@ skipping 108 matching lines @@
     }
     if (_slots[ScaffoldSlots.floatingActionButton] != null) {
       RenderBox floatingActionButton = _slots[ScaffoldSlots.floatingActionButton];
       Size area = new Size(size.width - kButtonX, size.height - kButtonY);
       floatingActionButton.layout(new BoxConstraints.loose(area), parentUsesSize: true);
       assert(floatingActionButton.parentData is BoxParentData);
       floatingActionButton.parentData.position = (area - floatingActionButton.size).toPoint();
     }
   }
 
-  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);
       }
     }
   }
 
   void hitTestChildren(HitTestResult result, { Point position }) {
     for (ScaffoldSlots slot in [ScaffoldSlots.drawer, ScaffoldSlots.floatingActionButton, ScaffoldSlots.toolbar, ScaffoldSlots.statusBar, ScaffoldSlots.body]) {
       RenderBox box = _slots[slot];
       if (box != null) {
         assert(box.parentData is BoxParentData);
         if (new Rect.fromPointAndSize(box.parentData.position, box.size).contains(position)) {
@@ skipping 71 matching lines @@
   void syncRenderObject(Widget old) {
     super.syncRenderObject(old);
     _toolbar = syncChild(_toolbar, old is Scaffold ? old._toolbar : null, ScaffoldSlots.toolbar);
     _body = syncChild(_body, old is Scaffold ? old._body : null, ScaffoldSlots.body);
     _statusBar = syncChild(_statusBar, old is Scaffold ? old._statusBar : null, ScaffoldSlots.statusBar);
     _drawer = syncChild(_drawer, old is Scaffold ? old._drawer : null, ScaffoldSlots.drawer);
     _floatingActionButton = syncChild(_floatingActionButton, old is Scaffold ? old._floatingActionButton : null, ScaffoldSlots.floatingActionButton);
   }
 
 }