title: AndEngine: Fatal exception in GLThread: IndexOutOfBoundsException
body: <p>I'm writing a custom dialog window for my AndEngine's BaseGameActivity and sometimes, when dialog have to dissapear, app crashes with this error:</p>
  
  <pre><code>08-15 09:49:16.193: ERROR/AndroidRuntime(1572): FATAL EXCEPTION: GLThread
          java.lang.IndexOutOfBoundsException: Invalid index 3, size is 3
          at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:251)
          at java.util.ArrayList.get(ArrayList.java:304)
          at org.anddev.andengine.entity.Entity.onManagedDrawChildren(Entity.java:1008)
          at org.anddev.andengine.entity.Entity.onDrawChildren(Entity.java:1000)
          at org.anddev.andengine.entity.Entity.onManagedDraw(Entity.java:993)
          at org.anddev.andengine.entity.scene.Scene.onManagedDraw(Scene.java:233)
          at org.anddev.andengine.entity.Entity.onDraw(Entity.java:875)
          at org.anddev.andengine.engine.Engine.onDrawScene(Engine.java:517)
          at org.anddev.andengine.engine.Engine.onDrawFrame(Engine.java:509)
          at org.anddev.andengine.opengl.view.RenderSurfaceView$Renderer.onDrawFrame(RenderSurfaceView.java:154)
          at org.anddev.andengine.opengl.view.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:617)
          at org.anddev.andengine.opengl.view.GLSurfaceView$GLThread.run(GLSurfaceView.java:549)
  </code></pre>