When a Picker's DialogTitle has a BorderRadius, the Picker title area does not get hidden as it should

[ThomasH99]

With 7.0.250 (but I think also before only I never noticed), the Picker's title area does not get hidden (despite being set to setVisible(false) in the Picker initialization).

I noticed this because I changed the DialogTitle css in a way that made it very visible (I changed it because the DialogTitle is also used for normal Dialogs).

With the test code below, tap the picker to see the scroll wheels, then in the Simulator check the Picker's title area and you can see its preferredSize is 108x108, so it's height get allocated above the Picker itself. (as can be seen in the screenshot below).

The CSS:

DialogTitle {
    border-radius: 2mm 2mm 0 0;
}

Test code:

                Form form = new Form("Test Picker", new BoxLayout(BoxLayout.Y_AXIS));
                Picker datePicker = new Picker();
                datePicker.setType(Display.PICKER_TYPE_DATE);
                form.add(datePicker);
                form.show();