Rename RuntimeError to CyclicIntializationError, as per spec.

runtime/bin/vmstats/bargraph.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.vmstats;
 
 class BarGraph {
   CanvasElement _canvas;
   GraphModel _model;
   List<Element> _elements;
@@ skipping 13 matching lines @@
   BarGraph(this._canvas, this._elements) {
     var maxElements =
         (_canvas.width - LEFT_MARGIN - RIGHT_MARGIN) ~/ SAMPLE_WIDTH;
     _model = new GraphModel(maxElements);
     _model.addListener(drawGraph, null);
     drawBarGraph();
  }
 
   void addSample(List<int> segments) {
     if (segments.length != _elements.length) {
-      throw new RuntimeError('invalid sample size for graph');
+      throw new ArgumentError('invalid sample size for graph');
     }
     _model.addSample(segments);
   }
 
   void drawBarGraph() {
     // Draw chart's outer box.
     var context = _canvas.context2D;
     context.beginPath();
     context.strokeStyle = 'black';
     // The '2's are the width of the line, even though 1 is specified.
@@ skipping 171 matching lines @@
 
   int get length => _segments.length;
   int operator[](int i) => _segments[i];
 
   Iterator<int> get iterator => _segments.iterator;
 
   int total() {
     return _segments.fold(0, (int prev, int element) => prev + element);
   }
 }