Removed the openglui sample app.

samples/openglui/src/flashingbox.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.
-
-/**
- * A sample GL application.
- */
-library flashingbox;
-
-import 'gl.dart';
-
-WebGLRenderingContext gl = null;
-
-num r;
-num g;
-num b;
-
-void setup(canvas, int w, int h, int f) {
-  if (canvas == null) {
-    canvas = new CanvasElement(width: w, height: h);
-  }
-  gl = canvas.getContext("experimental-webgl");
-  r = 0;
-  g = 0;
-  b = 0;
-  resize(w, h);
-  window.requestAnimationFrame(update);
-  log("Done setup");
-}
-
-void resize(int width, int height) {
-  gl.viewport(0, 0, width, height);
-}
-
-void update(when) {
-  gl.clearColor(r, g, b, 1.0);
-  gl.clear(WebGLRenderingContext.COLOR_BUFFER_BIT |
-       WebGLRenderingContext.DEPTH_BUFFER_BIT);
-  r = r + 0.1;
-  if (r > 1) {
-    r = 0;
-    g = g + 0.1;
-  }
-  if (g > 1) {
-    g = 0;
-    b = b + 0.1;
-  }
-  if (b > 1) {
-    b = 0;
-  }
-  glSwapBuffers();
-  window.requestAnimationFrame(update);
-}
-