Feature or bug?

Here's a very simple example code:
Code:
ContentPanel view = new ContentPanel();

TextButton btn1 = new TextButton("1");
TextButton btn2 = new TextButton("2");

view.add(btn1);
view.add(btn2);

System.out.println("view.getWidgetCount() = " + view.getWidgetCount()); // = 1
RootLayoutPanel.get().add(view);
The problem is, only the last widget (btn2) is really rendered. getWidgetCount() returns 1, as if btn1 was never added.
If it's a feature (like "you have to add another panel wrapping all buttons") - what would be getWidgetCount() for?