Clean up a bunch of our Dart code.

sky/sdk/lib/framework/rendering/object.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 '../node.dart';
 import '../scheduler.dart' as scheduler;
 import 'dart:math' as math;
 import 'dart:sky' as sky;
 import 'dart:sky' show Point, Size, Rect, Color, Paint, Path;
 export 'dart:sky' show Point, Size, Rect, Color, Paint, Path;
 
 class ParentData {
   void detach() {
     detachSiblings();
   }
   void detachSiblings() { } // workaround for lack of inter-class mixins in Dart
   void merge(ParentData other) {
     // override this in subclasses to merge in data from other into this
     assert(other.runtimeType == this.runtimeType);
   }
   String toString() => '<none>';
 }
 
 const kLayoutDirections = 4;
 
-double clamp({double min: 0.0, double value: 0.0, double max: double.INFINITY}) {
-  assert(min != null);
-  assert(value != null);
-  assert(max != null);
-  return math.max(min, math.min(max, value));
-}
-
 class RenderObjectDisplayList extends sky.PictureRecorder {
   RenderObjectDisplayList(double width, double height) : super(width, height);
   void paintChild(RenderObject child, Point position) {
     translate(position.x, position.y);
     child.paint(this);
     translate(-position.x, -position.y);
   }
 }
 
 abstract class RenderObject extends AbstractNode {
@@ skipping 408 matching lines @@
     int count = 1;
     ChildType child = _firstChild;
     while (child != null) {
       result += '${prefix}child ${count}: ${child.toString(prefix)}';
       count += 1;
       child = child.parentData.nextSibling;
     }
     return result;
   }
 }