[Effen] put Node class above its superclasses

sky/framework/fn.dart

Index: sky/framework/fn.dart
diff --git a/sky/framework/fn.dart b/sky/framework/fn.dart
index efb3ac238a58647521b8721e3dd64a82a1181cd9..505c1a447a814d56439dba9d7f4fe901329a1066 100644
--- a/sky/framework/fn.dart
+++ b/sky/framework/fn.dart
@@ -52,29 +52,6 @@ class Style {
   Style._internal(this._className);
 }
 
-abstract class ContentNode extends Node {
-  Node content;
-
-  ContentNode(Node content) : this.content = content, super(key: content._key);
-
-  void _sync(Node old, sky.ParentNode host, sky.Node insertBefore) {
-    Node oldContent = old == null ? null : (old as ContentNode).content;
-    content = _syncChild(content, oldContent, host, insertBefore);
-    _root = content._root;
-  }
-
-  void _remove() {
-    _removeChild(content);
-    super._remove();
-  }
-}
-
-class StyleNode extends ContentNode {
-  final Style style;
-
-  StyleNode(Node content, this.style): super(content);
-}
-
 void _parentInsertBefore(sky.ParentNode parent,
                          sky.Node node,
                          sky.Node ref) {
@@ -194,6 +171,29 @@ abstract class Node {
   }
 }
 
+abstract class ContentNode extends Node {
+  Node content;
+
+  ContentNode(Node content) : this.content = content, super(key: content._key);
+
+  void _sync(Node old, sky.ParentNode host, sky.Node insertBefore) {
+    Node oldContent = old == null ? null : (old as ContentNode).content;
+    content = _syncChild(content, oldContent, host, insertBefore);
+    _root = content._root;
+  }
+
+  void _remove() {
+    _removeChild(content);
+    super._remove();
+  }
+}
+
+class StyleNode extends ContentNode {
+  final Style style;
+
+  StyleNode(Node content, this.style): super(content);
+}
+
 /*
  * RenderNodes correspond to a desired state of a sky.Node. They are fully
  * immutable, with one exception: A Node which is a Component which lives within