Deprecate Math object in corelib in favor of dart:math library.

samples/spirodraw/Spirodraw.dart

 // Copyright (c) 2012, 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.
 
 #library('spirodraw');
 
 #import('dart:html');
+#import('dart:math', prefix: 'Math');
 
 #source("ColorPicker.dart");
 
 void main() {
   new Spirodraw().go();
 }
 
 class Spirodraw {
   static double PI2 = Math.PI * 2;
   Document doc;
@@ skipping 181 matching lines @@
     back.clearRect(0, 0, width, height);
     refresh();
   }
 
   /**
    * Choose random settings for wheel and pen, but
    * leave fixed radius alone as it often changes
    * things too much.
    */
   void lucky() {
-    wheelRadiusSlider.valueAsNumber = Math.random() * 9;
-    penRadiusSlider.valueAsNumber = Math.random() * 9;
-    penWidthSlider.valueAsNumber = 1 + Math.random() * 9;
-    colorPicker.selectedColor = colorPicker.getHexString(Math.random() * 215);
+    var rand = new Math.Random();
+    wheelRadiusSlider.valueAsNumber = rand.nextDouble() * 9;
+    penRadiusSlider.valueAsNumber = rand.nextDouble() * 9;
+    penWidthSlider.valueAsNumber = 1 + rand.nextDouble() * 9;
+    colorPicker.selectedColor = colorPicker.getHexString(rand.nextDouble() * 215);
     start();
   }
 
   void drawFixed() {
     if (animationEnabled) {
       front.beginPath();
       front.setLineWidth(2);
       front.strokeStyle = "gray";
       front.arc(xc, yc, R, 0, PI2, true);
       front.closePath();
@@ skipping 76 matching lines @@
 
 int gcf(int n, int d) {
   if (n==d)
     return n;
   int max = Math.max(n, d);
   for (int i = max ~/ 2; i > 1; i--)
     if ((n % i == 0) && (d % i == 0))
       return i;
   return 1;
 }