Change size of BubbleComponent for Slider

[TheWaveWarden]

Upon further research, I came across this feature request:

FR: make the bubble component used for the Slider::popup display customizable

Right now we can only override its “paint” function but we have almost no control over its size or layout. A simple Rectangle<int> getSliderPopupLayout (Slider&) callback in the LAF would be enough. It could return a “Rectangle” relative to its Slider. We would like to make the popup display a minimum width to make it visually more stable in case of drastic value changes. Right now the popup changes it’s width dramatically and that simply looks ugly.

So I guess I’m on my own.