Remove one more use of mirrors: Components now have to explicitly sync their fields.

sky/sdk/lib/framework/components2/drawer.dart

Index: sky/sdk/lib/framework/components2/drawer.dart
diff --git a/sky/sdk/lib/framework/components2/drawer.dart b/sky/sdk/lib/framework/components2/drawer.dart
index 222be067875fcd463c3780e7928e06fcecda487c..7cffcf892dc583d48aa7dbcb182715c1e057566c 100644
--- a/sky/sdk/lib/framework/components2/drawer.dart
+++ b/sky/sdk/lib/framework/components2/drawer.dart
@@ -109,6 +109,13 @@ class Drawer extends AnimatedComponent {
   int level;
   DrawerController controller;
 
+  void syncFields(Drawer source) {
+    children = source.children;
+    level = source.level;
+    controller = source.controller;
+    super.syncFields(source);
+  }
+
   double _position;
 
   UINode build() {