Why is the slider LinearBar outline not included in the LookAndFeel draw?

General JUCE discussion
1

We have a LookAndFeel::drawlinearSlider() function, which allows you to control most aspects of the slider’s appearance. But why is the outline of a slider (as LinearBar or LinearBarVertical) outside of this function, almost tagged on like an afterthought, at the end of the Slider paint() function? :

    void paint (Graphics& g, LookAndFeel& lf)
    {
        if (style != IncDecButtons)
        {
            if (isRotary())
            {
                auto sliderPos = (float) owner.valueToProportionOfLength (lastCurrentValue);
                jassert (sliderPos >= 0 && sliderPos <= 1.0f);

                lf.drawRotarySlider (g,
                                     sliderRect.getX(), sliderRect.getY(),
                                     sliderRect.getWidth(), sliderRect.getHeight(),
                                     sliderPos, rotaryParams.startAngleRadians,
                                     rotaryParams.endAngleRadians, owner);
            }
            else
            {
                lf.drawLinearSlider (g,
                                     sliderRect.getX(), sliderRect.getY(),
                                     sliderRect.getWidth(), sliderRect.getHeight(),
                                     getLinearSliderPos (lastCurrentValue),
                                     getLinearSliderPos (lastValueMin),
                                     getLinearSliderPos (lastValueMax),
                                     style, owner);
            }

            if ((style == LinearBar || style == LinearBarVertical) && valueBox == nullptr)
            {
                g.setColour (owner.findColour (Slider::textBoxOutlineColourId));
                g.drawRect (0, 0, owner.getWidth(), owner.getHeight(), 1);
            }
        }
    }

If you wanted to make the outline thicker, for example, you cannot do it without modifying the JUCE source. (Well, I suppose you could draw a thicker one on top of it… and to get rid of it you could set the colour to transparent… but it just seems like an oversight.)

This should really be inside of LookAndFeel::drawlinearSlider().